I'm not sure if it's a deliberate thing or not, but the crosshair for the tanks jet engine gun is actually offset slightly to the right of where the beam actually goes. I'd suggest shifting it to the left so that it more correctly corresponds to the beam.
The problem is that the line from the camera through the crosshair isn't parallel to the line from the jet gun toward where it's shooting. They only intersect at one point. At SOME range it will be accurate. At close ranges it will be off in one direction, and at further ranges it will be off in the other direction. Inherent problem in 3rd-person shooters, or any game where the projectile doesn't come straight out of the camera. TF2 rocket launcher has the same issue
I would suggest that it be more intuitive to have this crosshari at the peak of the weapons range as opposed to some arbitrary mid-point.
Looking again, I'm actuaolly noticn gt hat the crosshair NEVER intersects, under any forseeable circumstance with the beam. It's small, but I really do think it deserves a fix pre-release.
