I'd switch "Cloaked in Shadow" for "Infusion of Shadow" if you intend to stealth often and want to manage your initiative better. Signet of Shadow is cool but in WvWvW will do you no good outside of traveling, you'd be better taking another useful utility instead, either the famous Shadow Refuge, which will grant you 12 stacks of might alone if you stay in it for the full duration by the way, Infiltrator's Signet (if you're still having a hard time with initiative) or Scorpion Wire if you happen to run a party (at least another buddy) and want to surprise your foe. I'd also use Fleet Shadow in Acrobatics (you still get a huge amount of dodges with the 15 trait) and knock out 5 point of that line to get the 25 Deadly art trait which will increase your overall damage by 10% since every single foe you'll target will have a condition, thanks to the venoms and bleeds from pistol.
's what I have in mind.
I actually thought about a viable Venom build, but I don't want to re-gear for it. I run a S/D might stacking build however and the idea of getting more might through venoms has crossed my mind many times.