a “Preferences” dialog box would be a plus for the overall settings of the application to replace menus which are beginning to lengthen… We could find there, for example, the choice of the microphone (source) for the new function of voice recording; the choice of the organization of the interface; interface color; the default project folder; video settings…
Shotcut uses a Settings menu. I think it is better than a dialog.
a menu for setting the choice of the source to record the voice in the next version?
You should use Open Other for that so that you verify it is working and the audio level is good.