Forgive the haphazardly thrown in city block there. I just threw something down quick to test the scale. I wanted to see how the mountain assets would look on a smaller scale. I'm pretty happy with it. You can really really push the limits of depth. I could imagine the things you can do with tiered cities, and it's pretty exciting!
For trees/vegetation, I think the simple "spotted" brush/assets looks the best. If you aren't zooming in to a level to distinguish individual trees, this looks great. Then I added some fog in the valley shelf below just for kicks.
Let me know what you guys think of these types of trees and if it's something I should continue to peruse.
EIDIT: I added a second pic with a more detailed style of trees. These look a lot more like a tree canopy at the city level I think.