diff --git a/src/libs/utils/qtcsettings.h b/src/libs/utils/qtcsettings.h
index fd4841a961b..782d78c1052 100644
--- a/src/libs/utils/qtcsettings.h
+++ b/src/libs/utils/qtcsettings.h
@@ -38,6 +38,8 @@ public:
 
     template<typename T>
     void setValueWithDefault(const QString &key, const T &val, const T &defaultValue);
+    template<typename T>
+    void setValueWithDefault(const QString &key, const T &val);
 };
 
 template<typename T>
@@ -49,4 +51,13 @@ void QtcSettings::setValueWithDefault(const QString &key, const T &val, const T
         setValue(key, QVariant::fromValue(val));
 }
 
+template<typename T>
+void QtcSettings::setValueWithDefault(const QString &key, const T &val)
+{
+    if (val == T())
+        remove(key);
+    else
+        setValue(key, QVariant::fromValue(val));
+}
+
 } // namespace Utils
diff --git a/src/plugins/coreplugin/coreplugin.cpp b/src/plugins/coreplugin/coreplugin.cpp
index 937e18c7649..268b6997966 100644
--- a/src/plugins/coreplugin/coreplugin.cpp
+++ b/src/plugins/coreplugin/coreplugin.cpp
@@ -295,7 +295,8 @@ void CorePlugin::setEnvironmentChanges(const EnvironmentItems &changes)
     Environment systemEnv = m_instance->m_startupSystemEnvironment;
     systemEnv.modify(changes);
     Environment::setSystemEnvironment(systemEnv);
-    ICore::settings()->setValue(kEnvironmentChanges, EnvironmentItem::toStringList(changes));
+    ICore::settings()->setValueWithDefault(kEnvironmentChanges,
+                                           EnvironmentItem::toStringList(changes));
     if (ICore::instance())
         emit ICore::instance()->systemEnvironmentChanged();
 }
diff --git a/src/plugins/coreplugin/dialogs/newdialog.cpp b/src/plugins/coreplugin/dialogs/newdialog.cpp
index c42649c7290..73a4e41ebe0 100644
--- a/src/plugins/coreplugin/dialogs/newdialog.cpp
+++ b/src/plugins/coreplugin/dialogs/newdialog.cpp
@@ -484,9 +484,9 @@ void NewDialog::saveState()
     const QModelIndex idx = m_filterProxyModel->mapToSource(filterIdx);
     QStandardItem *currentItem = m_model->itemFromIndex(idx);
     if (currentItem)
-        ICore::settings()->setValue(QLatin1String(LAST_CATEGORY_KEY),
-                                    currentItem->data(Qt::UserRole));
-    ICore::settings()->setValue(QLatin1String(LAST_PLATFORM_KEY), m_ui->comboBox->currentData());
+        ICore::settings()->setValue(LAST_CATEGORY_KEY, currentItem->data(Qt::UserRole));
+    ICore::settings()->setValueWithDefault(LAST_PLATFORM_KEY,
+                                           m_ui->comboBox->currentData().toString());
 }
 
 static void runWizard(IWizardFactory *wizard, const QString &defaultLocation, Id platform,
diff --git a/src/plugins/coreplugin/dialogs/settingsdialog.cpp b/src/plugins/coreplugin/dialogs/settingsdialog.cpp
index 24c78b6513e..7efee37f4e3 100644
--- a/src/plugins/coreplugin/dialogs/settingsdialog.cpp
+++ b/src/plugins/coreplugin/dialogs/settingsdialog.cpp
@@ -755,7 +755,9 @@ bool SettingsDialog::execDialog()
         exec();
         m_running = false;
         m_instance = nullptr;
-        ICore::settings()->setValue(kPreferenceDialogSize, size());
+        ICore::settings()->setValueWithDefault(kPreferenceDialogSize,
+                                               size(),
+                                               QSize(kInitialWidth, kInitialHeight));
         // make sure that the current "single" instance is deleted
         // we can't delete right away, since we still access the m_applied member
         deleteLater();
diff --git a/src/plugins/coreplugin/documentmanager.cpp b/src/plugins/coreplugin/documentmanager.cpp
index e967e999c7f..a061d09c072 100644
--- a/src/plugins/coreplugin/documentmanager.cpp
+++ b/src/plugins/coreplugin/documentmanager.cpp
@@ -70,6 +70,7 @@
 #include <QMenu>
 #include <QMessageBox>
 
+static const bool kUseProjectsDirectoryDefault = true;
 static Q_LOGGING_CATEGORY(log, "qtc.core.documentmanager", QtWarningMsg)
 
 /*!
@@ -182,7 +183,7 @@ public:
     bool m_postponeAutoReload = false;
     bool m_blockActivated = false;
     bool m_checkOnFocusChange = false;
-    bool m_useProjectsDirectory = true;
+    bool m_useProjectsDirectory = kUseProjectsDirectoryDefault;
 
     QFileSystemWatcher *m_fileWatcher = nullptr; // Delayed creation.
     QFileSystemWatcher *m_linkWatcher = nullptr; // Delayed creation (only UNIX/if a link is seen).
@@ -1366,14 +1367,16 @@ void DocumentManager::saveSettings()
         recentEditorIds.append(file.second.toString());
     }
 
-    QSettings *s = ICore::settings();
-    s->beginGroup(QLatin1String(settingsGroupC));
-    s->setValue(QLatin1String(filesKeyC), recentFiles);
-    s->setValue(QLatin1String(editorsKeyC), recentEditorIds);
+    QtcSettings *s = ICore::settings();
+    s->beginGroup(settingsGroupC);
+    s->setValueWithDefault(filesKeyC, recentFiles);
+    s->setValueWithDefault(editorsKeyC, recentEditorIds);
     s->endGroup();
-    s->beginGroup(QLatin1String(directoryGroupC));
-    s->setValue(QLatin1String(projectDirectoryKeyC), d->m_projectsDirectory.toString());
-    s->setValue(QLatin1String(useProjectDirectoryKeyC), d->m_useProjectsDirectory);
+    s->beginGroup(directoryGroupC);
+    s->setValueWithDefault(projectDirectoryKeyC, d->m_projectsDirectory.toString());
+    s->setValueWithDefault(useProjectDirectoryKeyC,
+                           d->m_useProjectsDirectory,
+                           kUseProjectsDirectoryDefault);
     s->endGroup();
 }
 
@@ -1403,8 +1406,8 @@ void readSettings()
         d->m_projectsDirectory = settingsProjectDir;
     else
         d->m_projectsDirectory = FilePath::fromString(PathChooser::homePath());
-    d->m_useProjectsDirectory = s->value(QLatin1String(useProjectDirectoryKeyC),
-                                         d->m_useProjectsDirectory).toBool();
+    d->m_useProjectsDirectory
+        = s->value(QLatin1String(useProjectDirectoryKeyC), kUseProjectsDirectoryDefault).toBool();
 
     s->endGroup();
 }
diff --git a/src/plugins/coreplugin/find/findplugin.cpp b/src/plugins/coreplugin/find/findplugin.cpp
index c87d6c9cfdc..20219c16bef 100644
--- a/src/plugins/coreplugin/find/findplugin.cpp
+++ b/src/plugins/coreplugin/find/findplugin.cpp
@@ -130,14 +130,18 @@ static inline QString completionSettingsFlagsKey() { return QStringLiteral("Flag
 
 void CompletionModel::writeSettings(QSettings *settings) const
 {
-    const int size = m_entries.size();
-    settings->beginWriteArray(completionSettingsArrayPrefix(), size);
-    for (int i = 0; i < size; ++i) {
-        settings->setArrayIndex(i);
-        settings->setValue(completionSettingsTextKey(), m_entries.at(i).text);
-        settings->setValue(completionSettingsFlagsKey(), int(m_entries.at(i).findFlags));
+    if (m_entries.isEmpty()) {
+        settings->remove(completionSettingsArrayPrefix());
+    } else {
+        const int size = m_entries.size();
+        settings->beginWriteArray(completionSettingsArrayPrefix(), size);
+        for (int i = 0; i < size; ++i) {
+            settings->setArrayIndex(i);
+            settings->setValue(completionSettingsTextKey(), m_entries.at(i).text);
+            settings->setValue(completionSettingsFlagsKey(), int(m_entries.at(i).findFlags));
+        }
+        settings->endArray();
     }
-    settings->endArray();
 }
 
 void CompletionModel::readSettings(QSettings *settings)
@@ -380,15 +384,17 @@ bool Find::hasFindFlag(FindFlag flag)
 
 void FindPrivate::writeSettings()
 {
-    QSettings *settings = ICore::settings();
+    QtcSettings *settings = ICore::settings();
     settings->beginGroup(QLatin1String("Find"));
-    settings->setValue(QLatin1String("Backward"), bool(m_findFlags & FindBackward));
-    settings->setValue(QLatin1String("CaseSensitively"), bool(m_findFlags & FindCaseSensitively));
-    settings->setValue(QLatin1String("WholeWords"), bool(m_findFlags & FindWholeWords));
-    settings->setValue(QLatin1String("RegularExpression"), bool(m_findFlags & FindRegularExpression));
-    settings->setValue(QLatin1String("PreserveCase"), bool(m_findFlags & FindPreserveCase));
+    settings->setValueWithDefault("Backward", bool(m_findFlags & FindBackward), false);
+    settings->setValueWithDefault("CaseSensitively", bool(m_findFlags & FindCaseSensitively), false);
+    settings->setValueWithDefault("WholeWords", bool(m_findFlags & FindWholeWords), false);
+    settings->setValueWithDefault("RegularExpression",
+                                  bool(m_findFlags & FindRegularExpression),
+                                  false);
+    settings->setValueWithDefault("PreserveCase", bool(m_findFlags & FindPreserveCase), false);
     m_findCompletionModel.writeSettings(settings);
-    settings->setValue(QLatin1String("ReplaceStrings"), m_replaceCompletions);
+    settings->setValueWithDefault("ReplaceStrings", m_replaceCompletions);
     settings->endGroup();
     m_findToolBar->writeSettings();
     m_findDialog->writeSettings();
diff --git a/src/plugins/coreplugin/find/findtoolbar.cpp b/src/plugins/coreplugin/find/findtoolbar.cpp
index e2fe1038efb..912da4100e2 100644
--- a/src/plugins/coreplugin/find/findtoolbar.cpp
+++ b/src/plugins/coreplugin/find/findtoolbar.cpp
@@ -894,14 +894,20 @@ void FindToolBar::resizeEvent(QResizeEvent *event)
 
 void FindToolBar::writeSettings()
 {
-    QSettings *settings = ICore::settings();
-    settings->beginGroup(QLatin1String("Find"));
-    settings->beginGroup(QLatin1String("FindToolBar"));
-    settings->setValue(QLatin1String("Backward"), QVariant((m_findFlags & FindBackward) != 0));
-    settings->setValue(QLatin1String("CaseSensitively"), QVariant((m_findFlags & FindCaseSensitively) != 0));
-    settings->setValue(QLatin1String("WholeWords"), QVariant((m_findFlags & FindWholeWords) != 0));
-    settings->setValue(QLatin1String("RegularExpression"), QVariant((m_findFlags & FindRegularExpression) != 0));
-    settings->setValue(QLatin1String("PreserveCase"), QVariant((m_findFlags & FindPreserveCase) != 0));
+    Utils::QtcSettings *settings = ICore::settings();
+    settings->beginGroup("Find");
+    settings->beginGroup("FindToolBar");
+    settings->setValueWithDefault("Backward", bool((m_findFlags & FindBackward) != 0), false);
+    settings->setValueWithDefault("CaseSensitively",
+                                  bool((m_findFlags & FindCaseSensitively) != 0),
+                                  false);
+    settings->setValueWithDefault("WholeWords", bool((m_findFlags & FindWholeWords) != 0), false);
+    settings->setValueWithDefault("RegularExpression",
+                                  bool((m_findFlags & FindRegularExpression) != 0),
+                                  false);
+    settings->setValueWithDefault("PreserveCase",
+                                  bool((m_findFlags & FindPreserveCase) != 0),
+                                  false);
     settings->endGroup();
     settings->endGroup();
 }
diff --git a/src/plugins/coreplugin/find/findtoolwindow.cpp b/src/plugins/coreplugin/find/findtoolwindow.cpp
index e25a0d33c66..e689242941d 100644
--- a/src/plugins/coreplugin/find/findtoolwindow.cpp
+++ b/src/plugins/coreplugin/find/findtoolwindow.cpp
@@ -299,9 +299,10 @@ void FindToolWindow::replace()
 
 void FindToolWindow::writeSettings()
 {
-    QSettings *settings = ICore::settings();
-    settings->beginGroup(QLatin1String("Find"));
-    settings->setValue(QLatin1String("CurrentFilter"), m_currentFilter ?  m_currentFilter->id() : QString());
+    Utils::QtcSettings *settings = ICore::settings();
+    settings->beginGroup("Find");
+    settings->setValueWithDefault("CurrentFilter",
+                                  m_currentFilter ? m_currentFilter->id() : QString());
     foreach (IFindFilter *filter, m_filters)
         filter->writeSettings(settings);
     settings->endGroup();
diff --git a/src/plugins/coreplugin/find/searchresultwindow.cpp b/src/plugins/coreplugin/find/searchresultwindow.cpp
index 133a5a47ed3..bb61b2dda59 100644
--- a/src/plugins/coreplugin/find/searchresultwindow.cpp
+++ b/src/plugins/coreplugin/find/searchresultwindow.cpp
@@ -116,7 +116,7 @@ namespace Internal {
         QToolButton *m_expandCollapseButton;
         QToolButton *m_newSearchButton;
         QAction *m_expandCollapseAction;
-        static const bool m_initiallyExpand = false;
+        static const bool m_initiallyExpand;
         QWidget *m_spacer;
         QLabel *m_historyLabel;
         QWidget *m_spacer2;
@@ -130,6 +130,8 @@ namespace Internal {
 
     };
 
+    const bool SearchResultWindowPrivate::m_initiallyExpand = false;
+
     SearchResultWindowPrivate::SearchResultWindowPrivate(SearchResultWindow *window, QWidget *nsp) :
         q(window),
         m_expandCollapseButton(nullptr),
@@ -630,9 +632,11 @@ void SearchResultWindow::readSettings()
 */
 void SearchResultWindow::writeSettings()
 {
-    QSettings *s = ICore::settings();
-    s->beginGroup(QLatin1String(SETTINGSKEYSECTIONNAME));
-    s->setValue(QLatin1String(SETTINGSKEYEXPANDRESULTS), d->m_expandCollapseAction->isChecked());
+    Utils::QtcSettings *s = ICore::settings();
+    s->beginGroup(SETTINGSKEYSECTIONNAME);
+    s->setValueWithDefault(SETTINGSKEYEXPANDRESULTS,
+                           d->m_expandCollapseAction->isChecked(),
+                           SearchResultWindowPrivate::m_initiallyExpand);
     s->endGroup();
 }
 
diff --git a/src/plugins/coreplugin/generalsettings.cpp b/src/plugins/coreplugin/generalsettings.cpp
index 9ceb1752dd1..80822675ac1 100644
--- a/src/plugins/coreplugin/generalsettings.cpp
+++ b/src/plugins/coreplugin/generalsettings.cpp
@@ -96,8 +96,8 @@ GeneralSettingsWidget::GeneralSettingsWidget(GeneralSettings *q)
     } else {
         const bool defaultValue = Utils::HostOsInfo::isWindowsHost();
         m_ui.dpiCheckbox->setChecked(ICore::settings()->value(settingsKeyDPI, defaultValue).toBool());
-        connect(m_ui.dpiCheckbox, &QCheckBox::toggled, this, [](bool checked) {
-            ICore::settings()->setValue(settingsKeyDPI, checked);
+        connect(m_ui.dpiCheckbox, &QCheckBox::toggled, this, [defaultValue](bool checked) {
+            ICore::settings()->setValueWithDefault(settingsKeyDPI, checked, defaultValue);
             QMessageBox::information(ICore::dialogParent(),
                                      tr("Restart Required"),
                                      tr("The high DPI settings will take effect after restart."));
diff --git a/src/plugins/coreplugin/mainwindow.cpp b/src/plugins/coreplugin/mainwindow.cpp
index 5d7d9f12bee..6ec5f7eaa14 100644
--- a/src/plugins/coreplugin/mainwindow.cpp
+++ b/src/plugins/coreplugin/mainwindow.cpp
@@ -1027,6 +1027,8 @@ static const char windowGeometryKey[] = "WindowGeometry";
 static const char windowStateKey[] = "WindowState";
 static const char modeSelectorLayoutKey[] = "ModeSelectorLayout";
 
+static const bool askBeforeExitDefault = false;
+
 void MainWindow::readSettings()
 {
     QSettings *settings = PluginManager::settings();
@@ -1041,7 +1043,7 @@ void MainWindow::readSettings()
                                   QColor(StyleHelper::DEFAULT_BASE_COLOR)).value<QColor>());
     }
 
-    m_askConfirmationBeforeExit = settings->value(askBeforeExitKey, false).toBool();
+    m_askConfirmationBeforeExit = settings->value(askBeforeExitKey, askBeforeExitDefault).toBool();
 
     {
         ModeManager::Style modeStyle =
@@ -1068,13 +1070,17 @@ void MainWindow::readSettings()
 
 void MainWindow::saveSettings()
 {
-    QSettings *settings = PluginManager::settings();
+    QtcSettings *settings = PluginManager::settings();
     settings->beginGroup(QLatin1String(settingsGroup));
 
     if (!(m_overrideColor.isValid() && StyleHelper::baseColor() == m_overrideColor))
-        settings->setValue(QLatin1String(colorKey), StyleHelper::requestedBaseColor());
+        settings->setValueWithDefault(colorKey,
+                                      StyleHelper::requestedBaseColor(),
+                                      QColor(StyleHelper::DEFAULT_BASE_COLOR));
 
-    settings->setValue(askBeforeExitKey, m_askConfirmationBeforeExit);
+    settings->setValueWithDefault(askBeforeExitKey,
+                                  m_askConfirmationBeforeExit,
+                                  askBeforeExitDefault);
 
     settings->endGroup();
 
diff --git a/src/plugins/coreplugin/navigationwidget.cpp b/src/plugins/coreplugin/navigationwidget.cpp
index 4986a6a90ae..05bce9431dc 100644
--- a/src/plugins/coreplugin/navigationwidget.cpp
+++ b/src/plugins/coreplugin/navigationwidget.cpp
@@ -401,15 +401,25 @@ void NavigationWidget::closeSubWidget()
     }
 }
 
-void NavigationWidget::saveSettings(QSettings *settings)
+static QString defaultFirstView(Side side)
+{
+    return side == Side::Left ? QString("Projects") : QString("Outline");
+}
+
+static bool defaultVisible(Side side)
+{
+    return side == Side::Left;
+}
+
+void NavigationWidget::saveSettings(QtcSettings *settings)
 {
     QStringList viewIds;
     for (int i=0; i<d->m_subWidgets.count(); ++i) {
         d->m_subWidgets.at(i)->saveSettings();
         viewIds.append(d->m_subWidgets.at(i)->factory()->id().toString());
     }
-    settings->setValue(settingsKey("Views"), viewIds);
-    settings->setValue(settingsKey("Visible"), isShown());
+    settings->setValueWithDefault(settingsKey("Views"), viewIds, {defaultFirstView(d->m_side)});
+    settings->setValueWithDefault(settingsKey("Visible"), isShown(), defaultVisible(d->m_side));
     settings->setValue(settingsKey("VerticalPosition"), saveState());
     settings->setValue(settingsKey("Width"), d->m_width);
 
@@ -431,8 +441,9 @@ void NavigationWidget::restoreSettings(QSettings *settings)
     }
 
     const bool isLeftSide = d->m_side == Side::Left;
-    QLatin1String defaultFirstView = isLeftSide ? QLatin1String("Projects") : QLatin1String("Outline");
-    QStringList viewIds = settings->value(settingsKey("Views"), QStringList(defaultFirstView)).toStringList();
+    QStringList viewIds = settings
+                              ->value(settingsKey("Views"), QStringList(defaultFirstView(d->m_side)))
+                              .toStringList();
 
     bool restoreSplitterState = true;
     int version = settings->value(settingsKey("Version"), 1).toInt();
@@ -459,9 +470,9 @@ void NavigationWidget::restoreSettings(QSettings *settings)
 
     if (d->m_subWidgets.isEmpty())
         // Make sure we have at least the projects widget or outline widget
-        insertSubItem(0, qMax(0, factoryIndex(defaultFirstView.data())));
+        insertSubItem(0, qMax(0, factoryIndex(Id::fromString(defaultFirstView(d->m_side)))));
 
-    setShown(settings->value(settingsKey("Visible"), isLeftSide).toBool());
+    setShown(settings->value(settingsKey("Visible"), defaultVisible(d->m_side)).toBool());
 
     if (restoreSplitterState && settings->contains(settingsKey("VerticalPosition"))) {
         restoreState(settings->value(settingsKey("VerticalPosition")).toByteArray());
diff --git a/src/plugins/coreplugin/navigationwidget.h b/src/plugins/coreplugin/navigationwidget.h
index e1a2efed19f..7d18acba58b 100644
--- a/src/plugins/coreplugin/navigationwidget.h
+++ b/src/plugins/coreplugin/navigationwidget.h
@@ -36,6 +36,10 @@ class QSettings;
 class QAbstractItemModel;
 QT_END_NAMESPACE
 
+namespace Utils {
+class QtcSettings;
+}
+
 namespace Core {
 class INavigationWidgetFactory;
 class Command;
@@ -87,7 +91,7 @@ public:
     void setFactories(const QList<INavigationWidgetFactory*> &factories);
 
     QString settingsGroup() const;
-    void saveSettings(QSettings *settings);
+    void saveSettings(Utils::QtcSettings *settings);
     void restoreSettings(QSettings *settings);
 
     QWidget *activateSubWidget(Utils::Id factoryId, int preferredPosition);
diff --git a/src/plugins/coreplugin/outputwindow.cpp b/src/plugins/coreplugin/outputwindow.cpp
index ae0cb36c003..e41989143ae 100644
--- a/src/plugins/coreplugin/outputwindow.cpp
+++ b/src/plugins/coreplugin/outputwindow.cpp
@@ -145,7 +145,7 @@ OutputWindow::OutputWindow(Context context, const QString &settingsKey, QWidget
     connect(this, &QPlainTextEdit::copyAvailable, copyAction, &QAction::setEnabled);
     connect(Core::ICore::instance(), &Core::ICore::saveSettingsRequested, this, [this] {
         if (!d->settingsKey.isEmpty())
-            Core::ICore::settings()->setValue(d->settingsKey, fontZoom());
+            Core::ICore::settings()->setValueWithDefault(d->settingsKey, fontZoom(), 0.f);
     });
 
     connect(outputFormatter(), &OutputFormatter::openInEditorRequested, this,
diff --git a/src/plugins/coreplugin/patchtool.cpp b/src/plugins/coreplugin/patchtool.cpp
index be530e6a0af..1fdb9a34baa 100644
--- a/src/plugins/coreplugin/patchtool.cpp
+++ b/src/plugins/coreplugin/patchtool.cpp
@@ -53,9 +53,9 @@ QString PatchTool::patchCommand()
 
 void PatchTool::setPatchCommand(const QString &newCommand)
 {
-    QSettings *s = ICore::settings();
+    Utils::QtcSettings *s = ICore::settings();
     s->beginGroup(QLatin1String(settingsGroupC));
-    s->setValue(QLatin1String(patchCommandKeyC), newCommand);
+    s->setValueWithDefault(QLatin1String(patchCommandKeyC), newCommand, QString(patchCommandKeyC));
     s->endGroup();
 }
 
diff --git a/src/plugins/coreplugin/progressmanager/progressmanager.cpp b/src/plugins/coreplugin/progressmanager/progressmanager.cpp
index 39e78468e59..8840a85112a 100644
--- a/src/plugins/coreplugin/progressmanager/progressmanager.cpp
+++ b/src/plugins/coreplugin/progressmanager/progressmanager.cpp
@@ -56,6 +56,7 @@
 
 static const char kSettingsGroup[] = "Progress";
 static const char kDetailsPinned[] = "DetailsPinned";
+static const bool kDetailsPinnedDefault = true;
 static const int TimerInterval = 100; // 100 ms
 
 using namespace Core;
@@ -250,8 +251,8 @@ ProgressManagerPrivate::~ProgressManagerPrivate()
 void ProgressManagerPrivate::readSettings()
 {
     QSettings *settings = ICore::settings();
-    settings->beginGroup(QLatin1String(kSettingsGroup));
-    m_progressViewPinned = settings->value(QLatin1String(kDetailsPinned), true).toBool();
+    settings->beginGroup(kSettingsGroup);
+    m_progressViewPinned = settings->value(kDetailsPinned, kDetailsPinnedDefault).toBool();
     settings->endGroup();
 }
 
@@ -661,9 +662,9 @@ void ProgressManagerPrivate::progressDetailsToggled(bool checked)
     m_progressViewPinned = checked;
     updateVisibility();
 
-    QSettings *settings = ICore::settings();
-    settings->beginGroup(QLatin1String(kSettingsGroup));
-    settings->setValue(QLatin1String(kDetailsPinned), m_progressViewPinned);
+    QtcSettings *settings = ICore::settings();
+    settings->beginGroup(kSettingsGroup);
+    settings->setValueWithDefault(kDetailsPinned, m_progressViewPinned, kDetailsPinnedDefault);
     settings->endGroup();
 }
 
diff --git a/src/plugins/coreplugin/rightpane.cpp b/src/plugins/coreplugin/rightpane.cpp
index 67504b9a4a0..5b46581cf8d 100644
--- a/src/plugins/coreplugin/rightpane.cpp
+++ b/src/plugins/coreplugin/rightpane.cpp
@@ -28,7 +28,7 @@
 #include <coreplugin/imode.h>
 #include <coreplugin/modemanager.h>
 
-#include <QSettings>
+#include <utils/qtcsettings.h>
 
 #include <QVBoxLayout>
 #include <QSplitter>
@@ -171,26 +171,20 @@ void RightPaneWidget::resizeEvent(QResizeEvent *re)
     QWidget::resizeEvent(re);
 }
 
-void RightPaneWidget::saveSettings(QSettings *settings)
+static const bool kVisibleDefault = false;
+static const int kWidthDefault = 500;
+
+void RightPaneWidget::saveSettings(Utils::QtcSettings *settings)
 {
-    settings->setValue(QLatin1String("RightPane/Visible"), isShown());
-    settings->setValue(QLatin1String("RightPane/Width"), m_width);
+    settings->setValueWithDefault("RightPane/Visible", isShown(), kVisibleDefault);
+    settings->setValueWithDefault("RightPane/Width", m_width, kWidthDefault);
 }
 
 void RightPaneWidget::readSettings(QSettings *settings)
 {
-    if (settings->contains(QLatin1String("RightPane/Visible")))
-        setShown(settings->value(QLatin1String("RightPane/Visible")).toBool());
-    else
-        setShown(false);
+    setShown(settings->value(QLatin1String("RightPane/Visible"), kVisibleDefault).toBool());
+    m_width = settings->value("RightPane/Width", kWidthDefault).toInt();
 
-    if (settings->contains(QLatin1String("RightPane/Width"))) {
-        m_width = settings->value(QLatin1String("RightPane/Width")).toInt();
-        if (!m_width)
-            m_width = 500;
-    } else {
-        m_width = 500; //pixel
-    }
     // Apply
     if (RightPanePlaceHolder::m_current)
         RightPanePlaceHolder::m_current->applyStoredSize(m_width);
diff --git a/src/plugins/coreplugin/rightpane.h b/src/plugins/coreplugin/rightpane.h
index 030d7a08d2d..a0ea919a04e 100644
--- a/src/plugins/coreplugin/rightpane.h
+++ b/src/plugins/coreplugin/rightpane.h
@@ -36,6 +36,10 @@ QT_BEGIN_NAMESPACE
 class QSettings;
 QT_END_NAMESPACE
 
+namespace Utils {
+class QtcSettings;
+}
+
 namespace Core {
 
 class RightPaneWidget;
@@ -65,7 +69,7 @@ public:
     RightPaneWidget();
     ~RightPaneWidget() override;
 
-    void saveSettings(QSettings *settings);
+    void saveSettings(Utils::QtcSettings *settings);
     void readSettings(QSettings *settings);
 
     bool isShown();
diff --git a/src/plugins/coreplugin/themechooser.cpp b/src/plugins/coreplugin/themechooser.cpp
index 62db2eb8189..9ef53718443 100644
--- a/src/plugins/coreplugin/themechooser.cpp
+++ b/src/plugins/coreplugin/themechooser.cpp
@@ -177,11 +177,13 @@ void ThemeChooser::apply()
     if (index == -1)
         return;
     const QString themeId = d->m_themeListModel->themeAt(index).id().toString();
-    QSettings *settings = ICore::settings();
+    QtcSettings *settings = ICore::settings();
     const QString currentThemeId = ThemeEntry::themeSetting().toString();
     if (currentThemeId != themeId) {
         // save filename of selected theme in global config
-        settings->setValue(QLatin1String(Constants::SETTINGS_THEME), themeId);
+        settings->setValueWithDefault(Constants::SETTINGS_THEME,
+                                      themeId,
+                                      QString(Constants::DEFAULT_THEME));
         RestartDialog restartDialog(ICore::dialogParent(),
                                     tr("The theme change will take effect after restart."));
         restartDialog.exec();