Pretty much agree with what's been said but regarding the forests (which is really what you seemed to be looking for) it seems a bit flat. You might want to generate some cloud noise beneath the forested areas to give them some depth so it's not quite so one-colored. Might want to hit it with some burn/dodge as well. Noise can also create little flecks that can look a bit like leaves if you tint them correctly.

I like they layout you have going with the land and so on, keep up the good work.