This game is awesome! Really love the art style and the squishy isometric angles, the space garden felt really cool and I think was a good pick for a lot of music! I could see this being expanded into a full rhythm game with it's own music and climactic boss fights. So satisfying seeing everything bounce and glow in time with the music too!
Only thing I'd recommend is maybe having the level up rewards be able to be selected with the 1-2-3-4 keys or something, and available on the side? Picking an upgrade (and reading what they all do) can feel kind of disruptive when you're jamming out!