The cliffs are no longer bald! I've added trees and shrubs, some of which are still floating out in the ether, but they'll be grounded soon. I painted some of the shrubs by loading a palette knife with paint and scraping it against the textured "rock" - the texture broke the green paint up into natural-looking foliage.
I also brightened the cliff faces with more color washes. The subtle iridescent gold paint that I mixed in with the other colors doesn't want to show up in photos - but in the right light, it gives a little bit of glimmer to the sandstone cliffs.
In other news, I've started a Facebook business page for my art...if you're a member of Facebook, you should join as a fan to follow updates! :)