Pics pics pics! Hows it look?
I think 2 percs will be tough for a small tank because they'll pollute the water fairly quickly. Best thing I can see is to invest in a BakPak-like skimmer if you want to keep them as a skimmer will help you out tremendously. Do some searching for skimmers here on RC--especially check out Anthony Calfo's sticky thread in his forum about skimmer improvements--to really get the most out of your skimmer if you decide to use one.
And I agree about the damsel. It will most likely just be hassle down the road. Invest in more compatible corals--that will play nice with each other--instead of fish. Crabs, snails, shrimp are good additions as well. On small tanks, fish typically cause more problems than they're worth. I've got a blue velvet damsel in my 50g against a larger gold striped maroon clown. I'm hoping the maroon vs the BVD will be a good fighting pair for the future. Great color combo.
A comment about the rockscaping, create overhangs if you can. Go with some smaller branchlike rocks on the bottom with the larger rocks on top of them to minimize dead spots in the tank. If you do this, add a lot of circulation for brisk underwater movement. 20-30x turnover would be prime with an efficient skimmer taking out all organics and baddies. Remember, just my comments.
But yeah, pics would be nice to see how things look. Good luck man. I'll follow this thread and help you out if I can from my Exp. I know how it feels making your best efforts even if they are mistakes.