I was frost for a long time but saw a good 500 dps increase by going to arcane. I run a mixed group so I need to keep things as simple as possible.

#showtooltip Arcane Blast
/use 13
/use 14
/castrandom Icy Veins, Mirror Image
/script UIErrorsFrame:Clear()
/castsequence [target=focustarget,exists,harm,nochanneling] reset=combat/target/4 Arcane Blast, Arcane Blast, Arcane Blast, Arcane Missiles

character is Havelnostra on Lothar