The game is short but fun, and the visuals are really inspired and captivating. I also liked a lot the fact that you carefully guide the player so he doesn't feel lost, and, let me tell you, the ending was trippy
As for the feedback:
the controls, especially the jump, fells a bit sluggish. It becomes very evident when you are trying to reach an elevated platform
you can get soft-locked: to me, it happened right after the castle, since i used the key to open the door back (I thought I'd find some sort of secret)
moving objects, like cannonballs and balloons seem to be parented to the player, so they then to follow/get away from you. I don't know if this is intended, but it doesn't look right