I'd recommend the first 8 points in shield something like this. If you want to, move around the 1st row points how you like. The important part is the second row. Following, crawl how you like. The best trees are shield & assault. Respecs reset on Tuesday after patch. It will say the old price and you need the $, but it won't take the $.
Personally I would not try assault in PVP until you have 18 points. That's when it really starts to pay off with high impact bolt procs. And of course, 21 points gets you 60% more HIB armor penetration..
Some strong pvp builds
21/2/18 -- look it up, "carolina parakeet" build. google it.
8/2/31 -- ion cell + assault plastique
("2" in the middle tree for HIB 40% penetration. love to put 3 in here, but sadly can't afford it.. storm & assault plastique make the build. but "3" in the middle tree while leveling is a strong choice!).
In my opinion, the best PVP spec abilities (in no order):
- storm.
- root on harpoon.
- assault plastique.
- HIB 90% armor penetration & procs.
- stockstrike, especially proc'n HIBs (18 points in assault). 30% more crit/damage is nice though.
- hold the line (if you are good at kiting, variable range... and ok with less dps).
Try them all. The style/ability you feel most engaged with is the one for you. They're all at least somewhat viable so respec often and find your niche.
More opinion:
- assault gets better with good gear, and when you get 31 point ability.
- parakeet is great while leveling.
- tactics dps sucks... but moving fast is fun.