I'm currently trying to develop a tileset that's slightly reminiscent of early Pokemon games and other topdown early RPGs and roguelike games. The tile size I've been using is 16x16, and my program of choice is Pyxel Edit. Right now, I'm trying to figure out a way of improving the forms without pushing the color count high, and am also trying to work on the composition of the attached picture.

Any tips on composition of the mockup/ tips on making the individual tiles better looking?