Well after about 70ish 2v2 games as holy pally / prot pally, we got to around 1850ish mmr average for the most part. We generally have my partner (the holy) just keep us up till we run the other team out of mana or untill we can get a focus burst on the healer. Double DPS teams are a joke considering nither of us can easliy be bursted down and we have defensive cooldowns / dispells for each other to break CC. However healer + dps teams can be increadably long fights with us generally running them out of mana, and we have had a stale mate with a 2200 rated druid rogue with the arena match closing on us after 45mins.
Most fights are either over within a few seconds or incredibly long.
However last week i tried 3v3, and man is it a different story. We joined my freinds team which was at around 1550ish rating when we started and in 2 nights we were able to play ~80 games and get the team to 2k i think our MMR is around 2200ish so when we can find time to play a few more this week we will see how it goes.
We are running holy pally / prot pally / rogue, which is rather unique but has given us some good synergy surprisingly. Our rogue is able to stay hidden untill the other team opens up on ither the holy pally or myself at which point we are able to time our burst / stun / sheild throw silence / arcane torrent and kill just about any healer that can't get us peeled off of them.
Prots burst is utterly amazing combined with the silence that sheild toss brings. The downside is once your inital burst is up your not doing nearly as much damage for another 30 seconds for stun / sheild toss to come off of cooldown, however in 3v3 if you have a partner with an MS effect and can lay on a bit more dps you can take down just about anything.
I'm logged out in my pve gear / spec, but for the most part im in t9.25 ret chest/gloves, t9.25 prot helm / legs, relentless belt, boots, bracers, darkmoon card greatness, the AP wintergrasp trinket.
If you have any other questions let me know i'll try to answer them the best I can, I am by no means an expert at this spec or arena but i'm giving it my best for the moment