I seemingly lost control of my characters after doing a stage and trying a different one? I couldn't move the pair anymore, although I could still click on menu buttons. Not sure if it's a known bug or something I missed. I was playing the offline Windows version, in case that's important.
As many have said before, the aesthetic is impeccable, but the gameplay is hard to learn, let alone master. I also don't think it was all that necessary to have big "beams" to avoid on top of everything else.
I'd like to add, and this is really just my own opinion and has no bearing on my rating, that I don't quite think Keine and Mokou fit as the "protags" in this kind of game. I think Touhous with a musical inclination, like the Prismrivers, Raiko or the Tsukumos, would fit better without context, or even someone like Wriggle because of how some insects "dance".
This isn't to say I didn't enjoy Mokou and Keine being used here (I could see a case of Keine convincing Mokou to try it and having to either play as Keine to teach Mokou, or Mokou having to struggle to learn), just that I think some context would have done wonders to me why the two are dancing at all, and feels like a missed opportunity.