Your main account has a couple of 80s you could use for boosting as well, that could speed things up greatly. I dont know how well Warriors do, but if you have any feral gear for your resto druid then bear + swipe = win.

Also Prot Pallys do very well, level 78 should have very decent gear for boosting pre 60.

As for what to bring up...
2 Pallys would be good, you already have one on the main account so you would end up with 3 of them, same with Rogues and Mages.
I really enjoyed my mages and look forward to playing them again when I finish leveling my dungeon team. So I would say ensure you get at the least the Pallys and mages to 60 during your RAF time.