That's one of the best looking setup I've ever seen. One thing I have tried and I think I'll experiment a little more with is styrofoam. I took a block of styrofoam, carved it to look like a cliff side. I even cut in a cave for my viper gecko to hide in. He never goes in it though. He likes to hide between the top of the foam and the top of the cage.
I need to find some kind of sealant or paint the I'm sure will be safe, to make it more like rock. I've seen it done before but I don't know what they use. If anybody knows please let me know.