My best setup ive tried though is pure dps 4 shamans with a boomkin. Sounds weird but you get the moonkin aura and mow so you get two buffs one adds health and mana other increases spell damage plus all four can heal. I mean chain heal and dots plus mad dps is insane. I know in a pvp setting most will go straight after moonkin cause they will think thats the main so i always put him as the last one in my group to switch to.