Thanks Tim, Mini,
I think I have found a final form I happy with. Not going to be representative of a certain landscape but I think there are nice points of tension. I tried to follow rule of thirds.
The back left rock presents as steady and relaxed. Rock to the front right creates tension as does the one behind it with its leaning position. Mostly epiphytes and some mixed grasses. Maybe stems or long grass species on the very left back.