I like the coastline style you're developing in the upper left. I think you should maybe start at a higher resolution, as the trees and swamp symbols seem oversized for this size a map. Then again, I've seen some antique maps that look just like that, so maybe not. Are you creating your own symbols or gathering them from elsewhere? The line qualities are quite variable. I think you should shoot for a line weight that's similar to the surf line on your coast and the rivers in the left-hand part of the map. As it stands now, most of the mountains appear blurry and indistinct. And perhaps a bit too small when placed alongside those trees.
I like the way you're heading with this. It reminds me a bit of some maps I've seen from… I think maybe the 15th century. I don't recall for sure.