I started with 5 elemental shamans but got my ass kicked in RFC, so I changed it to 1 prot paladin and 4 shamans. Since then I've been getting better (and so has my gear) and the paladin is pretty useless now... the shamans kill everything before it even gets to the tank. But it changes again when you want to do heroics... so the tank helps in getting started in instances at lower levels, then isn't really needed again until 60ish

The paladin is the main, yes. I click most of his buttons and have hotkeys for all the shaman stuff.