I would do a Paladin and Druid, with 3 man im going to guess your going to be leveling via non instances primarily and cashing in on the 3x xp quest turn ins from the RAF. Druid gives you a great buff with MotW and a damage shield. Healing wont be a problem as both the druid and pally can heal. Pick any easy to follow dps class, Mage or warlock or something that has a lot of instant cast dps because things are going to be dead before you wind up your second or third casting of anything else.