The general feel of the thing is good - I think it would look better if the mountains were more gradual. Like, some smaller mountains around the big peaks, and some little hills around the smaller mountains.

Also, there's a little bit of a visible pattern in your forests - I think you're using the thing where you put down big blocks of trees, right? Unless I'm drastically wrong, there's also an individual tree icon - try using that to break up the repetition.