Thinking of leveling my Priest (85)

My Priest was going to be my main for MoP, but I decided against it for a better raid comp (RL friends, 10man).

Now that we've all taken a break, and admittedly lost interest in the game, I've been staring at it wanting to level it. There is about 3-4 of us left, and I feel that if I level a healer it will dramatically help our guild search, since we are all primarily DPS. I've been eyeing up Monkey Runs since they're still viable for leveling, and am not sure if I should heal them to 90 as holy or disc. I haven't played a healer since early TBC, since then I've been DPS on a number of classes, I'm thinking a change to a healer will be dramatic enough to re-spark my interest in the game... but I'm not sure what to expect.

Any thoughts on what I can expect out of going from a DPS to a Healer in PVE? I've been 2400 on a few characters in arena's as well, but what will it be like switching to a healer for this? Does anyone have any experience? Most of my friends were healers since vanilla or TBC, and when the chance to swap to DPS arose, they took it and never looked back. Will that happen for me, but in reverse?

Thanks for any help you can provide.