My idea du jour...

[adameros]

This would be a global change, so I'm expecting this to be shot down (no pun intended)...

Barrel vibrations. Like many FPS games, when you have the sniper riffle and the barrel moves around a bit, so you have to time your shots. I would like something like that when you use your binoculars (easily explained away as engine vibrations, or the thumpin' bass from your tanks over powered subwoofer). Then you could have a "barrel stabilizer" (or BS flag... *insert joke here*) that would make the barrel rock solid like it is now.

The goal is to make it harder to laser snip from clear across the map.

[blast]

Sounds too complicated for the game.

[Quantum Tank]

BZflag is about geometry, not physics. I think if people remembered this (admittedly generalized) concept, we would have fewer over-complicated suggestions.