I love the concept! Having bullets forming this choreography, instruments represented in different shapes… It's really beautiful, and fun to play!
However one thing I'm really not fan is the instant death. I've found the act of repeating the beginning of the song quite frustrating, and in the end haven't been able to complete the game. The beginning is also punitive very early: the two waves are pretty difficult to dodge, and the dash more than often throw into another bullet. I enjoy difficulty, but it doesn't always have to be punitive.
But this choice aside, it's still a really good game! I enjoyed getting as far as I could.