5 x ele shamans

[Ualaa]

Well, with 5x Shammies, you can experiment.
For battlegrounds, 5x Fire Elemental or staggered... with a 5 min cooldown (glyphed) is quite nice AoE power, especially if you are swarmed.

As you pvp and gain honor, and buy gear (wait until the next season starts, and its better gear for the same cost), your resilience goes up, which is staying power.
With 5x Shammies for heals + healing stream totems, you become quite a force.
AV is generally a really good BG; a lot love EotS too.

[Littleburst]

You shouldn't expect anything aslong as you don't got atleast 600 resi or so.

My suggestion is to get full stormhide at lvl 78 and do AV. you just need time played to get used to the 5 shamans, with full stormhide you got a good chunck of hp and 300ish resi. I did this quadboxing 4 shaman and got Wrecking ball( 20 Killing blows without a death) and Damage Control (300k dmg done to players) in the same AV, as an example. This is much more enjoyable (easier) then lvl 80 pvp, because people are leveling, they're here for exp and fun. Besides that most people run around with 0 resi, so they die like flies. 4 x magma + fire nova on every CD and TS to finish it off is great aoe damage on melee.

At 80 a well played pvper in full relentless using everything he can to annoy you can be extremely frustrating.