I worked out a lot of different specs in PvP, I tried and discounted a lot of the builds posted on the forums because I could find better, you have to realise that a lot of it was just people playing with the calculators and thinking they had found a great build when they weren't 50 yet.
When I was undergeared this was by far the best build I had:
http://www.torhead.com/skill-calc#601rcrokrskdZhGbMzZz.1
I used a shield instead of Focus and the rest of my gear was all dps gear.
I could be stupidly survivable, amazing at defending a node. And back in the day before crazy gear, level 50 bracket and higher expertise I wouldn't think twice about taking on 3 people to capture a node.
Use Force Potency on 3 stacks of Harnessed Shadows or for when you need to stop a cap on a node up to 30m. You get loads of free kills in Hutt Ball with Force Pull, especially from stealth. And you can do some real flair moves jumping in to the pit before the touchdown zone and Force Pulling as you fall to take the ball carrier with you.
Sit in Combat Technique, only use Guard when you have a good healer with you because you will be focused a lot.
Always keep Kinetic Ward up.
1v1 I would only lose to Clairvoyant Strike shadows amusingly and Operatives that opened on me.
This build has been buffed since the days when I used to use it with Combat Technique changes, I tried it again and swapped back quickly when I realised the groups I go with needed the higher dps.