My favorite cloud is the sunny one ! But hail cloud is cool too.
I think there is a bug if you click too fast on continue in the tutorial the screen goes gray and you can't do anything (I did it the second time I went to the tutorial because there was only one point I had forgotten and I remembered the rest so I skipped it very fast and it caused the bug I think).
Gameplay wise, I don't really play bullet hell games (and I'm bad at them) so I don't know if it is an intended feature or not but the map is finite, I was stuck against an invisible wall at some point.
The art is not the greatest but it had its charm, I like it, and each cloud has its own personality that's really nice. Also the art style is very consistent which makes everything look better and cohesive, except for the big smileys they clash too much with the rest I would suggest you to remove them.