Eh . . . Sniper rifles COULD be an intresting twist on the normal gameplay, but I think there's more potential for harm than good. I feel like BOTH the sniper missions ((Before the Storm and Shot in the Dark) are poorly balanced and I rarely play them online. When I do, it is out of desperation for new ground from the fact that I've played all the others to death. (I'm not complaining that there aren't enough, EIB has TONS of MP levels, I just play WAY too much.)
That said, I imagine that if BOTH sides were given a SINGLE sniper in a city type level it could be a blast. It would be balanced because each side has a sniper. The key would be to give the regular squads plenty of buildings to move through to keep the snipers from being killing machines, or at least deny the snipers a position with a clear shot at a large swath of the map without exposing themselves to the other sniper.
That is still a little dangerous though because each dead sniper leaves behind a scoped weapon and it could very easily degenerate into a sniper war. Maybe if the snipers spawned with limited ammo for their scoped weapon. (That would also dampen the killing machine effect because they would have to be more careful with their shots.)
I don't really care about the multiplayer part of the game, what I love about it is the singleplayer part. And I'd like to see sniper rifles too, maybe a bit more often than in the earlier games.
----------------------- That which can be imagined need never be lost. - Weaveworld, Clive Barker