Thanks for playing, and for taking the time to give recommendations. For the theme, it was just meant to be that you can move with two keys at a time, so that's why I allowed other keys such as E and R. I absolutely agree that there should have been instructions, I just ran out of time to better display them in game.
Doing better art and making the music were a bit of a trial run for this game, since I usually work in a team, and don't do those. I think that the art in this one ended up a lot better than it has in previous games where I did the art, and the purple was kind of the theme I was going for, but the background probably should have been different. I'll tackle more variety next time ; ). For the music, I agree that it was a bit short. That was more of a time crunch issue, and a lack of skill in creating long songs. Personally I liked where the keys were since you can hit E if you want to make them disappear, and look at the map, but that wasn't properly explained in game. If I update this post jam, I'll probably either shift them, make them semi-transparent, or add an option to press M which zooms out and views the whole map. Anyways, thanks for your input, and I hope that you were able to have some fun with it!