I understand both sides of the fence.
Firstly, I'm a lethality sniper. Seriously sick dps if you know what you're doing but it takes a *long* time to get used to the appropriate combo to avoid getting major energy management issues. Also, you really don't spend a huge amount of time in cover in this build, sure you want some...but it's not where the majority of your dps comes from.
As I'm only valor 59 I can't be the be-all-end-all in PvP, but even as such when competing against everyone else for the WZ dps charts I am *always* top 3-4, usually top 2.
As to utility, sure I moan about how ****** our utility is compared to others in the game for PvP...but we have got: Leg Shot for a 0 resolve snare, Flashbangs - AoE stun, a decent cooldown on shield probe and cover pulse and that's just for starters.
Perhaps we don't have the leaps or what have you, but unless you've built your skills wrong the only thing I *regularly* complain about is the necessity to be in cover for our knockback (that just blows).
Lethality tree, being majority internal damage, tears through the tankiest of opponents. It's not an easy class to play, but they are by no means weak.
(also if you're waiting on a 2.5 sec ambush in marksman spec then you're playing the class wrong, take some time to work on your skill rotations)