Disc priest partner

I've played rogue since vanilla retail and I've always ran with the same disc priest. I stopped playing on Outland for a while and have decided to come back but I wanna try something other than rogue. I'm torn between mage, enhance shaman and warlock.

I don't know if warlock would work well with a disc priest. My thought on it was to treat it as a double DPS and keep one feared while we both DPS his partner. I know frost mage works fairly well. I'm also unsure how enhance shaman would work. Any thoughts or input would be appreciated.

Mage or lock works well.
I don't think a Enh would fit though. They are quite bad for 2s.
U could also consider to go with a mm hunter as a mana melting comb.