QFileDialog: suggestions to improvement of the non-native dialog on Windows

It would be nice if the QFileDialog could be improved regarding the following:

When using the QFileDialog::getExistingDirectory(...) with the option QFileDialog::DontUseNativeDialog on Windows:

• The Combo Box displays the entry "My Computer" twice after opening the dialog with an UNC-path.

• Entering an UNC-path into the Line Edit requires quite a long time, since with each letter the dialog checks, if the corresponding computer exists.
  (if (!info.exists() ...) in Line 2370 in qfiledialog.cpp)

• Pressing return after a file-path was entered closes the dialog instead of displaying the corresponding directory in the window upon the Line Edit.

• The symbols (My Computer, ...) at the left have no windows-style. We miss the typical windows symbols "Recent Places", "Desktop" (as in the QFileDialog::getOpenFileName(...)).

• There is no possibility to adjust the Qt::WindowFlags.

Using the regular QFileDialog constructor causes the same problems (except the last item).