/ic/ - Artwork/Critique

So, I am trying to get into painting and I am doing this thingy, but I don't really know exactly where to go from here.

I blocked in the colors on the background, still figuring out the characters, of course, but about the background, should I start rendering details? My first instinct is to start fixing the edges on the trees and to start to render the leaves, but I don't want to jump into details too early. What do you guys think?