Here is a minor one. In spritebatch draw, add dual layer sort options. FrontToBack + Texture and BackToFront + Texture. So if a group of images (A,B,A,B,A,B) drawn on 0.5f layer. It will group all of them on 0.5f then secondary by texture so it can batch it more efficiently so (A,A,A,B,B,B) on layer 0.5f.