I'm with parrotchute, I like how the rock looks now too, nice and open...but, we've all been there where we stare and stare and something (to us) just isn't right and we're not going to be happy til it's different.
I think dry rock would be the way to go for sure...tonga branch would mix it up, and a bridge, you got lots of good suggestions!
I got some awesome dry tonga branch from brs, kinda mixes it up from just lumps of rock. Not that my rockwork is anything to look at right now :)