Here is a Ficus Too Little Forest Rock Planting I did at a Club workshop(Kawa Bonsai, Bunnell Fl) with Rodney Clemons, who is from Atlanta, GA last Friday night (June 15, 2012).
Defoliated because I took a lot of roots off. They are already popping back. As for the rocks, they might change a little, this is actual three lava / pumice rocks. I am thinking of adding some moss and other plantings on the rock and make this more penjin then bonsai. Thanks for your comments.
I agree with the others -- the rock should go. It's a mismatch "sizewise" (too small to be a mountain, too large (compred to the trees) to be a boulder); it is too centered in the composition.
Did you put the rock in at the workshop? I'd guess that Rodney would suggest eliminating it, too.
Nice rock but, IMO, it should go--it really detracts from the trees, especially since it's such a similar color as their trunks/branches. I also agree the size doesn't work. If it were me, I'd keep it simple. Bet you'll find the perfect use for that rock in another planting.....