3xDruids is nice because you can run any combination of Tank, Healer, or Ranged DPS that you may need. Healer and Ranged DPS can easily share gear, too.

If I was going to limit myself to a 3x setup, I'd go druids for sure. Come dual-spec switching, you can easily grab almost any two people and be able to instance run.

Strongly consider going quad accounts though, if you can. It's a nice step up...