I like it.

Did you create the forest or is that taken from an aerial photograph? It kind of looks like an actual photo which is pretty cool. The only thing about the forest that I'm not sure about is the way it fuzzy fades around the edges. Like jf said, with the other styles where everything has a solid edge you may want to try trimming down the blur around the forests just a bit.

That is an incredible wall the way it's perfectly straight going over the mountains and all. It seems like it should change in the up and down terrain, maybe some kind of shadows and highlights?

You may also want to try getting the brick like texture on your buildings to go in the direction of each building. What you have works but all the brickwork runs east west regardless of the direction of the building. It may just be a matter of selecting the building outlines on the right layer and using the rotate feature, building by building. It doesn't look bad the way it is but you might like the way it looks if you can do this.

I really like your coloring - It's rather Autumn-ish and warm. Keep up the good work, if you are like the rest of us you learn so much each time it's totally worth it.