This kinda degernated from the OP, but my two cents is go ret paly and enhance shammy for dual classes, but if one of you wants to be a healer go Holy paly enhance.
Everyone thinks they are kiteable, but not sure why, Imp Ghost Wolf means that with run increase boots you are as fast or faster then anyone(faster then people with out run increase) and thats with CCs on you. You hit them with FS and no one can run from you.
Even mages with frost nova arent a problem. Say they do the FN blink combo to get away from you, drop a grounding totem and wind shear their first cast. Totem will eat fire blast or any other instant and they will have done 0 dmg the whole time.
With ret paly this class really shines cause the combination of AoW procs for FoL if one of u needs or Exorcism if not, allows for great burst betweent he two of you. Don't think any other two classes could take down this combo, burst will kill one person even before a healer can heal and between purge and cleanse you guys are set.
Here is an armory of the gear i collected and specced for 49. A lot of it is shit mixed with BoA but I could take on groups of 3-4 solo and not have to worry too much. Only problem solo was ambush rogues if trinket/Gift of the Naruu were both on cd.
The World of Warcraft Armory basically you could get way better gear, but if possible I reccomend those maces. They wreck face at every lvl and at 51 they are better then the BiS twink gear from 59