sentinel isn't that bad, I soloed the entire story line, once you get doc it goes a lot faster. in pvp I typically am one of the top dps, granted thats expected as a lvl 50. you actually have great oh **** buttons to keep you alive, but they only buy a few seconds unless someone bothers to heal you. 1v1 actually can win most of the time if I have all my abilities up to counter their cc. I use the combat tree since it seems to have better burst.