Good day! Arma 3 in my opinion it is necessary:
Ability to throw grenades while running
Changing weapons during the run
Ability to lie on any surface, even if it is not suitable for this, the player begins to rise ARMA2 if the surface is not suitable for this (in a combat situation, I would not get up under fire if the surface is not suited for this)
The ability to shoot from vehicles sitting in place passengers on motorcycles, trucks and other vehicles
Requires a knife to each soldier, it lacks strong
Need reliable trajectory of anti-tank grenade, which did not correspond to reality in ARMA2, which makes the tanks are too vulnerable, the infantry must shake his knees at the sight of armored vehicles actually
And it is extremely necessary balance of arms in different directions, it is very lacking in ARMA 2!