First off, I am an observant n00b so what I say doesn't have to matter, but the way I see a lot of rainbow decks working is based on one equation; oty + firefly queen +firestorm + bonewall =win, graveyard and fallen elf/druid is just damage bonus eternity helps to not deck out as well but I do like to keep small decks so you can draw what you need quicker
i've been playing sg rainbow but i wanted to change things up a bit. i'm may put in 2 sor's and i have put in 2 sundials for a little card drawing and to slow the momentum of my oponent. The deck wins 80% of my games vs half bloods and with the exception of the usual suspects(sies, miracle,rainbow) can beat the gods but not nearly as consistent.