My biggest piece of advice would be to playtest fast and early with people who aren't working on the game! I agree with a lot of the other concerns here in the comments... it's not obvious that only Right Control works, and selecting the blocks can be pretty confusing. I think the core mechanic of being able to move the notes is super cool and it's audibly very satisfying, but from what I played it seemed like the best strategy was to just find a small block and... take that all the way to the end. Cute game though! +2 for petting the cat.