I don't like the proposed sniper changes. They range from too good to clunky.
After some testing, these are my thoughts on them, they're kind of raw, and I might edit the wording later.
Most sniper-archetypes could already get snipe as an instant-cast in bursts, such as when popping build up, aim, domination or simply by being in a team with +tohit buffs. Of course, you could build to have it up all the time, too. Now, everyone can do it all the time, and it's less impactful overall as a result.
The "Out of combat/in combat" dynamic is nonsensical. You'll maybe land one of the 'slow snipes' maybe once-a-mission. If nothing else is to change, this bit needs to go and the ability just needs to do X amount of damage. The whole point was that a character with good aim could fire instantly without taking a few seconds to aim.
It strikes me as a change that really didn't need to be made, and I think it takes the reward out of building your character properly.
Furthermore, non-sniping powersets will fall further behind, which, while I'm sure that can be addressed later, is an immediate issue that comes to mind when massive "everyone gets instant snipe" change is made.