2nd on the damsels. They are evil, if you can get rid of them, do it. I have two that I barely tolerate the other fish int the aquarium. Until I stop being so lazy and I get to an outdoor shop to buy a small hook & line, I'm stuck with them.
Maybe you could get some pajama cardinal fish (they're pretty cool to look at, but not very active) or a clownfish? Just make sure you do a lot of research before buying them so you don't get something that will be incompatible with something you want down the road....
You can probably get away with less live rock as long as your tank isn't stacked too quickly or heavily.. I started out with a lower than "ideal" amount, and slowly added base rock - former live rock that's a lot cheaper and will get "seeded" by the new rock.
-alex