Gearing part is not perfect; for mage rogue you either want to go with almost full pve set (like I do right now) or get 4/5 pvp set (+10 energy, awesome!).
Weakness spectralizers is great item, and you definitely want this. If you are meeting a lot of non-stealther teams, it's possible to go with other helms too (I do this with 4/5 tier7.5, and chestguard of recluse).