White rocks that are completely smooth remind me of a stream, but this doesn't have the look of a stream. So I say the white rocks should go.
Also you never know if they'll leech or give off stuff in your water.
You could do lots of driftwood with some more jagged rock, but those just don't look natural with your scape.
MABJ's iDevice used for this message :p
I've used them in other tanks with no problem. Hmmmm, I have lots of different sized lava rock I could try. Just trying to work with what I have, as much as I'd love to go spend $100 on rocks or wood, I can't. Big Al's boxing day sale already got me on other things I needed. lol. I'll play around and see what I can do or what else I have.