Couple things:

To start, what other people said does feel true. This game is more satisfying in terms of its generation aligning with the songs. It's fun, as well. But for this game to especially stand out and fulfill its potential, I'd suggest a few things.

PAUSING - As far as I can tell, there is no pause button. If you hit escape, in fact, it will take you back to the menu and suddenly end your round.

OPTIONS - There is no options menu. You cannot modulate volume nor view controls or otherwise in-game. Even if it seems small, having the ability to window, change resolution, arrange audio settings, all while staying in the game makes it a better flowing experience.

GRAPHICAL STYLE - The game's style is fine. However, to maximize potential, I think it would be best to have multiple visual style types to choose from. (The current one is a neon geometric 3D style, but it could benefit from other added styles both 3D and 2D, such as other color pallets, or enemy and obstacle looks.)

GAMEPLAY MODES (?) - Maybe other modes, such as boss rush in which you fight only bosses, or endless scrolling platformers, or traditional 4 key rhythm. Of course, this is a more sizable thing to request but it sounds fun so y'know why not throw that suggestion in.

MORE BOSSES - Besides the massive wall, I would love more bosses to add variety!

Otherwise, I'd give this game a solid 6.5/10. I think it's worth the five bucks to have a game that's as rare as this type of game (music-based procedural generation based on your music) can be.