Request 1: It would be cool if libraries could automatically add their own configuration settings to the game.project file. I noticed that the google analytics library requires you to open your game.project file with an external text editor and copy-paste some stuff into it. That works, but isn’t exactly ideal.
Request 2: Allow specifying the type of a setting, so the editor makes the right input widget for it. For example, clicking a checkbox is much nicer than typing “1” or “0” in a full-length text input box.
There is one old question about this: Custom checkbox in project settings file (game.project)
Requests 3 & 4: Specifying default values and tooltips for settings would be very nice too (but much lower priority).