I don't get how GS are bad, I roll a GS and I wreck in PVP. Not sure if you know this but GS are on par with TOP DPS. The reason why your getting targeted alot in pvp is because people know that GS are hard hitters, even against tanks I can still manage to reek havok on them.
I have a rotation I go with that gives me the best possible DPS as possible.
all I have to say about dying alot is to stay in cover, not sure if you know this but your defense goes up with you being in cover, so its a bad idea to start running at the first sign of trouble. Turn on your defense screen and dodge. you'll be invincible for 3 seconds, in which you can kick the other person's *** in that time and if you have it turn illegal mods on as well to increase your casting time between attacks, which makes getting a crit with charged shot alot easier, making your aimed shot alot shorter, to about 1.2 sec.
you just have to know how to play your cards right with GS, its a gamble with that class,
reason why it has cover is that its one of the hardest hitters in pvp than any other classes.