I would bench the Elemental shaman and the warrior. You can run a immunity comp with the classes you have there with the boomkin getting disperse from the spriest. Try the 2-2-3-3 strat (tank/melee, hunter/2 priests(give them the gateway), lock/boom/hpally, tank/melee). It will make the transitions a joke the hunter and spriest can babysit the disc and immune the rest of the stuff.