Suggestion : make total spare ammo scale depending on weapon.

[Shezo]

For example, take some random number, like 10k damage as potential damage per total spare ammo and divide it by damage per hit, and you'll get rough number of spare ammo for each weapon.

Shotguns will have less spare ammo, since they do a lot damage per hit and rapid-firing weapons, like braton or gorgon, will have more spare ammo.

You also can add to equation weapon accuracy, e.g less accurate weapon will have more ammo; burst damage, innate armor penetration and etc, all this more subtle characteristics.

And if ammo will be reworked this way, make ammo pickups restore ammo by percentage, like 5 percent per pickup or something like that.