you need a discord,
insane concept, you could add some options, like reverse arrow keys, or just press any key at the right time to progress, also change the overall speed of the song?
found few bugs
(like you can generate a new map when playing, if you click on the place where the button to generate one was, you can write in both speed X and Y at once and im sure theres more of them)
idk how hard it would be but you could try to put the entire thing into bigger engine or something, all there is is the generating, which is really cool, you could put it into unity and i dont think it will take that much time to get it done, you can then turn in into webGL build and anyone could play it from the browser
with unity you could add shaders and lighting in seconds which would improve the visuals by a ton!
i see huge potential and i feel like stealing the idea... i wish i would know how you did this
i hope youre not done with this project, keep going!!!