This would obviously be an optional choice, as some would not want to use the historical reticle. I can’t really show many examples, but here are some late/post Cold War ones.
(Some of these would “not be possible” in game because of the auto-ranging fire control system, or in other words, it will work, you would just have to implement that)
A few other things would be a “from gunner sight” view, which is already in game, but optional, I’d like to see this come to keep from a few cheeky spots you can shoot through and a few other issues with down bore sight. Also, another unpopular opinion, is giving barrels a collision with vehicles and objects.