Oh, this is a fantastic idea. I'm rubbish at rhythm/timing games, but when I got into the groove and managed to *hit* multiple times in a row felt *really* satisfying. And I adore the way you used the central spin mechanic for the menus as well. Actually adds some stakes to the shop. And I like that you get some coins even if you don't clear the level, makes it possible to have incremental progress, which feels really nice.
Well done!