Strange that noone has mentioned MM hunter.
I've been playing with random nongeared feral vs many comps and we were pretty good, same goes for my friend - nongeared ret. The idea behind MM+ret/feral is to get enemy team to dump focus/energy on ret/feral while I keep distance, if on low HP ret bubbles/feral jumps away.
MM damage in nothing to be sneezed at. Here is our match vs 28 MW + 20 elem, in the end we've forced MW OOM and killed him. Elem was healing MW almost all the time and MW was healing himself, but our combined damage output + mortal wounds debuff was too high.
http://i.imgur.com/SKWLSLB.jpg