Well it kinda looks like a display of sea shells and, as bobHe suggests, the fish will redecorate to suit themselves so it won't look like that for long! I'm not so sure whether some of those shells (particularly the cowries) are entirely suitable, you might double check in case there's a risk of the shellies getting stuck in them. From a practical point of view you're going to have a 'mare trying to syphon up around that lot to keep the lovely white substrate clean.
I'm not overly fond of the pseudo-saltwater look, but that's a personal preference. Lots of you North Americans seem to love it, is there something of the frustrated salty in you? More rocks would definitely be a good idea, I would steer clear of plants unless you go plastic.
You shouldn't be relying on that piece of rock alone to buffer your water, is that crushed coral substrate? What's your pH, KH and GH?
So where have the fish taken residence, brevis on the left and multies on the right or are they still sorting themselves out?
Good luck with it!