I'm really digging these graphics and the chaotic layout here.
Couple things to consider:
1. The gray looking tile on the right side which in the middle of the green and along the edge doesn't feel like it fits in with the rest of the graphics and mapping. Straight edges with rounding corners are your friend.
2. Too many bookcases being used. There's a good assortment of exterior blocks, but maybe need some more interior blocks. Clocks, pictures, plants, etc.