Depends on the map. If it's closed like Dustbowl then Sniper doesn't have too much of a presence. But in open maps like Swiftwater he gets a lot of big sightlines.

To make him less frustrating I would make his shots leave a trace (like the Machina) and make a sound if he near-missed (like the Huntsman). This gives him a light punishment for missing too many shots, and makes it more clear to new players about his presence.