Really sweet little adventure, most of the notes I'd have have already been raised by previous comments, size and scale of the levels being just a bit large etc.
But I do have some some game-feel things that jumped out at me though, the way that movement and every game object is on a grid makes perfect sense for this kind of game, but the smooth seamless movement animation makes it feel like you should be able to move on a diagonal or that things the player and rocks shouldn't be locked to grid positions, this makes it really easy to overshoot when holding down the directional inputs. Just adding a very brief pause between each "step" of movement would solve this handily I think.
All of the objects having their shadows be at different heights makes the perspective a little bit wonky for judging alignment, I know the art is from an asset pack, but it's likely an easy fix?