I play a 1500 RBG rated lock when I am not healing running as destro or occassionally affliction. For destro I like to use Conflagrate to slow opponents and build embers. If you are going destruction I would have a Havoc Macro to cast it on one target (Arena1-5) and then hard swap back to your kill target so 8 chaos bolts hit the two targets 4 to each... it is awesome when used in conjunction with any pvp trinkets, engineering, etc... and as a 25 second cool down should be used twice per minute to exert pressure via Chaos Bolt or any three single target spells.

Finally what level 90 talents are you looking at? I went with sacrifice to increase my health and damage by 20% or what ever. But for demo alot of them go with the 2 x pet macro for 20 seconds for more pressure.