Thank you a lot for your honest feedback.
Reviews like this are one of the reasons that I enjoy jams and creating stuff in general.
You have motivated me to work on the final version at some point in the future, as I also feel that there is a lot of potential with the game, even if I didn't manage to show it in the Jam. It was honestly a pain to make. The first few days were wasted trying to figure out the physics joins and weird physics errors/bugs, dunno how to call them, and because I didn't have enough time, I was trying to work on it from my actual job as well.
The final version will definitely have customisable controls, even if I have no idea why the separate NumPad isn't working. Will need to check it out when I implement them!