In my first non-Ironman playthrough, I had one sniper with Snapshot, one with Squad Sight. They both got more kills than anyone else. Squad Sight probably got more, but it can be extremely helpful to have a sniper who can adjust before taking a shot, especially if you also give him the Colonel perk that allows for shots to flanked/not-in-cover to not use up an action. If you get ambushed in close range, you can just have him move around, flanking the enemy, and take out every damned one in a single turn. It doesn't happen all that often, admittedly, but as I say - he still got more kills than any Heavy, Assault or Support soldier. Just have him sit slightly behind your frontline soldiers.

HEAVY / ASSAULT
SUPPORT
SNAPSHOTTER
- a stroll in the woods
- tumbleweed
- lost person asking for directions
- sign telling pointing in the direction of the enemy
SQUADSIGHT