As for scopes, I think they're fine. The only disadvantage snipers have is that you can't adjust ur sights whereas on the k98 u can just laser people from over 9000 feet away.
This is a funny problem, but not from the side of the engine but the players mind. While using an uscoped weapong on longrange you will aim a bit above the target. The fun fact is that, when you are aiming with a scoped weapon you will also aim above the target, but not enough. This is because of two things:
1. The target seems closer than it is through the scope, making you aim lower in general
2. You know at least a little by heart how high to aim with the unscoped version, you might aim as high with the scoped gun, resulting that you will actually aim lower due to the zoom
3. With zoom aiming as high as with the unzoomed view will look higher with zoom than without.
This is what makes aiming with scoped weapons feels to be harder then with unscoped ones. But with a little practice you will adjust this, resulting that you hit much better. Also you can actually see the impact of the bullet with the zoom, so you can adjust your aim, while without zoom you have to guess if you have to aim higher or lower.