This was really cool! Great art and music. The only suggestion I would have would to be to have the arrows or (WASD) labelled on the corresponding circle. It seems like a bit of a silly suggestion but whenever I've played rhythm games that element always seems to have the arrow keys shown - and for some strange reason not having those made this harder for me when there was a lot of music notes on the screen. But take that with a grain of salt because I'm pretty bad at this type of game.