Hey, thank you for the kind feedback :). And yeah, there is a huge issue with the rescale, because the game is in 1280x720, and in fullscreen in HD (1920x1080), it would be x1.5, so the pixel won't be square anymore. So we made the choice to lock the rescale only for whole number (1280x720 => 2560x1440, etc...), and we realize the very last day that our game won't fit for the most common screen : 1920x1080.
So our first big thing to do with the post-jam version is to make it in 640x360, to make it rescalable in almost every resolution :) (1280, 1980, 2560, etc...)