Im currently gearing up my 3x mages combo, only got 144 res and 650 spelldmg. For arena i find it hard ofc sins everyone ussualy have at LEAST full gladiator and abouve 250+ res. But i manage to winn games time to time, im pompyro (40/21/0) wich i find as the best specc for playing mages. I tryed frost for about 12 hours pvp + arena, but i didnt like it, its Really hard to use all Cooldowns and get propert shattercombos with 3. Well i gues its worth trying again sometime but i enjoy more to one-shot people =) it ussualy gets 3v2, then i sheep one and its 3v1 =).

In the BG its ussualy loleasy or lolhard, ither i meet 1 or i meet 10+. Still trying to defend GY's in AV to get like 3v4-5 situations but its really rare (reccing for my movie ^^).
But i will try serious with arena as soon as i get some propert gear. Untill then im happy if i can stay around 1500 rating xD.