How accurate do you think the 30% armor for bosses (assumption) you've set by default is? The Sith Sorcerer Madness thread seems to suggest it's 50% for bosses (and all champion mobs)

I may have been playing against terrible bounty hunters but are they the ones that spam.. Fusion Missile? or something like that? If so, interrupting it seems to nullify a lot of their damage. Otherwise, flashbang/debilitate until help arrives! Unless you're overgeared, snipers are primarily a support class

I've only done a few dailies with it but if you don't have access to a healing companion yet, I think you should stay with Marksman for PvE as Lethality lacks some of the upfront burst.

I made a video of some Level 50 WZ lethality gameplay: I feel it should be played a lot like a maneuverable DoT class whilst a MM sniper is pretty much a turret (I do similar amounts of damage with both specs though) Keep in mind many of the opponents don't have much expertise gear yet but IA's are fairly fragile as a whole.