I love the art style! But have a few nitpicks about it.
- Most surfaces have textures but the grass is just a solid colour and I think it stands out a lot
- The shadows are blurry which definitely does not conform to the game's art style. This can be fixed with a custom screenspace shadow shader that rounds shadows darkness to either 0 or 1
- Specular highlights give a feeling of smoothness, which not all surfaces should have. For example, the specular highlight (and solid colour) in the 2nd screenshot makes the grass look almost like plastic. This can be fixed by adding a texture and removing the highlight. In the 3rd screenshot, the floor seems to be made of bricks or planks, but because of the highlight, it makes it obvious that it's just a flat texture. A normal or bump map would work well here
Otherwise very well done, the clouds are gorgeous too. I realize the game was made for a jam, but I'm sure many people would appreciate a post-jam version of the game