Gonna double up on what CCinoWrath said below - offset and scroll speed settings would be massively appreciated for dealing with some of the more complex/compact strings of notes. I also felt like none of my notes had any impact - the song was unphased whether I flawlessly hit a combo of 50 notes or sat there doing nothing. Lastly I was kind of hoping for some twist to the basic rhythm game "hit the note" gameplay, something that made it feel more touhou, like dodging enemies to the beat (ex:Yoiyami Dancers).
The pixel art is well made and I like the concept - a Touhou rhythm game is a great idea and I hope gets more fleshed out!