i think it would be cool to have more bullet variety.
bullet type 1. less accuracy, less velocity, more sound and more muzzle flash but more damage.
bullet type 2. less accuracy, less velocity, more sound but less recoil.
bullet type 3. more accuracy, more velocity, less sound and less muzzle flash but worse recoil.
and then ill leave the rest for the devs to think of but just think of the variety that could be added. They don't have to be big changes for the bullets just more things that would be could to add to the game.