Okay so I have to preface this by saying. I really don't like sokoban games. I just don't find them very fun and it feels like more of a chore. So this isn't a criticism of your game, I just don't like this genre of game at all.
With that being said the design and style of this is really good I love the hand-drawn sketchy art it's simple but really well done.
I don't really get the idea behind having the player and the obstacles on different layers. It felt like an additional level of complexity that wasn't really needed in my opinion. But switching between the layers wasn't an issue so it wasn't a huge concern.