Hmm actually... we do have Evasion and Hunker Down. Evasion can save your life. Hunker down is good cc immunity but you have to stay stationary. When i see a sniper use hunker down, i just swap target or LoS him to force him to move. lol.
Even then, I still find Snipers to have some of the weaker cooldowns in comparison to most classes. Defense Probe is nothing to write home about and is on a 45 second cooldown unless you're Lethality or spec'd into Engineering to get the instant second probe from EMP Discharge (60 sec CD when spec'd into). Evasion only works on ranged and melee attacks making it worthless against some classes/specs (e.g. Sorc, Rage Warrior) as an upfront defense. Evasion's cleanse is more worthwhile than it's ranged/melee dodging ability in the majority of circumstances. Hunker Down is decent but only good as a defensive ability if spec'd into Marksman for the AOE reduction and extra duration.
As for offensive, Target Acquired is in an okay spot, but Laze Target is rubbish. I'm not complaining about our cooldowns as situationally they can be amazing, but they don't have as many general applications or game-changing potential as other classes' cooldowns. I'm in no position to sit here and claim Snipers require some new Bloodthirst because despite the lack of very effective all-purpose cooldowns, we're in a really good place overall at this moment. As what was stated before, we're just hoping to open dialogue about the possibility of altering cooldowns in the future, and not just asking for our own Sniper invincibility bubble.
This game and its other classes have much bigger issues than the Snipers getting new toys to place with.