There's a game called Call of Duty: Warzone. In this game are dozens of Assault Rifles, Pistols, SMG's, Sniper Rifles. With their own animations, sound effects, graphics, stats, etc. Conveniently, their stats, like damage, are very similar to the current items. I can absolutely use math to calculate proper stat adjustments to work within this game with it feeling natural and balaned. A very simple un-edited example: A Sniper Rifle from Warzone currently does 150 damage; kind of like the base-level hunting rifle doing 100 damage. Hopefully you guys can see what I'm getting at.