Your priest + any of those 70's is a good duo, war for tanking harder stuff, mage for AE'ing tons of stuff down while shielded and HOT'ed up, or with the hunter for keeping him and the pet alive.

As far as 3, You may want to roll a new setup, or at least 2 characters of the same class to run with your priest, lock-lock-priest, mage-mage-priest, or shm-shm-shm are all good.