My 7 fishes would be:
2 perculas
1 yellow tang
1 blue regal tang
1 flame angel
1 powder blue tang
1 purple tang or copperband butterfly or small red volitan lionfish
The reason that I wouldn't put any triggers and most butterflies is because they don't really belong in a reef tank and would in real life eat the clams and corals.
(Not good reasons in a virtual reef I guess). Also, all of those fishes that I listed are in my real reef tank at home, except for those on the last 2 lines.