Ranger duo?

[Sorrow*qc]

enchanter or necro, Snare + fear make it pretty easy

[Glaani]

Another vote for shaman. I had some very successful duos with a ranger back in the day.

[Shiro White]

I'd vote necro. Necro is already a beast while solo'n, so it can compensate for the weakness of ranger. Unlike something like a Mage though, ranger does have some synergy with the Necro, being able to melee things that are feared, provide snares so necro can spend mana on more efficient damage, and later on SoW the necro to save some money on SoW pots. Track's always nice too.

The necro will obviously level slower than solo due to that hefty hybrid penalty and the ranger not fully pulling it's weight, but best option I see.