Lovely work, Max! =) I love the colors, the subtle lines you used and the very tolkinesque look.
One thing you could try: The forest has thinner outlines and your mountains have lines as thick as coastlines. I'd try to tone them either down a bit or slim them down a little. Could be a lot of work, I see that (and maybe just toning them down is enough).

I'd love to see this finished =)
Cheers, Steffen