I use a build that's decent for PvP and PvE. It lags only a little bit behind 10/48/3 in PvE, but it's a lot better in PvE; I'm on a PvP server, i PvP a lot and i also do kara. Comment please.
Build: http://www.wowhead.com/?talent=obxVc0fzxIzrZxgGzb0co
1) I'm not changing Improved AM. I use them a lot, PVP they demolish casters, i use them to farm primal fire as well, and also in PvE when mana isn't a huge issue.
2) There's no possible way i'm touching Critical mass or Arcane instability.
Other then that, feel free to give me any kind of advice/criticism.
Arguments: I play like a fire mage. Main nuke is Fireball / Arcane blast (not with 3 buffs). AM is also used at times mana can be spared, and arcane power + PoM + 3 buffed AB + Pyro > AB spam to finish off bosses quickly (By burning mana i can get a DPS of around 1500).
Spell power really helps with ignite, heavy crits that give heavy ignites are great. Blast wave, Improved CS, Burning soul and Arcane subtlety help with PvP as well as PvE (because otherwise, AB spam would get me utterly murdered, and i use it on bosses a lot to do ~20k damage in a very short amount of time.
Improved fire blast is a godsend in PvP (and also kind of in farming, but that's a minor issue). Usually, i PvP by moving a lot, using blast wave/frost nova to my advantage, and peppering my target with fire blast and ice lance, AE if they're close, and fireball / AB spam if i have casting time. Against casters, i'll start with imp counterspell if they see it comming, then sheep, PoM AP pyro, followed by fire blast, then arcane missles do destroy their casting times (I actually killed a lock before he got a fear off because AM just kept pushing it back, he was damn well geared too.) My gear is decent (All blues, 3 epics), but not really good.
I have +660 spell damage self-buffed. I always use food + Wizard oil + Elixir of pure death for Raids, and just the elixir for when i arena/BG.