There's a small problem since it's quite easy to missclick the left side with Dai chan, story is quite funny, I would personally add a little bit of dialogue when they meet other characters, since it's quite silly that Cirno can't be melted completely in the middle of an onsen.
The thing here is just to maaaybe make the last puzzles a little bit harder since the core mechanic is just to push a few times and let gravity do the rest.
Still, great game, would play again.