I play a sniper and I'm a pvp fanatic. I don't know how many respecs I've tried, but the cost is getting rediculous. Sniper is a pure dps class. Marksmen is stationary burst (boring), engineering AoE/surviabilty, and lethality mobility/dot dmg. As of now a engineer/lethality hybred is the best spec for PvP. You can offer mobility dps in group situations.
Personally I would like to see a utility tree that utilizes CCs over dps. I'm too weak to carry a huttball and cc would make the class so much more fun. What do you snipers think? I want to bring this idea to the suggestion forums.