Thank you brother for the nice review.
Rhythm is an interesting idea to work with. But in my game there is a little problem, in future maybe i will work on this game and implement an upgrade system for player as well for enemies. And there is a key variable, movementRate which is use to determine how much frequent player move. So in my case i will also increase it as well if my player upgrades. So for that reason it can't be implemented.
Yeah, i will also add different types of enemies, more upgraded enemy ai. And a bigger map too.