since there are many class suggestions out there, i thought i might throw in my own ideas on the subject, this is an EXTREMELY simple class system
3 new things here:
Medpack: drop on ground, will despawn after 2 minutes, once picked up by a teammate it will bring their health back to 100
Supply box: drop on ground, will despawn after 2 minutes, once picked up if any teammate is low on ammo, blocks it will bring both ammo and blocks to regular
Pistol: does 40% the damage of the semi, and has less zoom and range.

Assault(SMG):smg/2 grenades/50 blocks
Sniper(Semi):Semi/2 grenades/50 blocks
Medic:Pistol/2 medpacks/50 blocks
Support:Pistol/2 supply boxes/80 blocks( blocks take 4 hits to take down as opposed to 3)