-Support on the idea that you can spawn breaching charges and gas. Unfortunately that would allow criminals to get their hands on it and /invholster it.
A good alternative that will allow you to get more ammo is https://steamcommunity.com/sharedfiles/filedetails/?id=893205646 it will provide you with more ammo for whatever weapon you are holding in your hand when you pick it up. (Including Gas, Breaching Charges, ect.)
The resetting the armor idea is sadly harder then it sounds. Since GMod does not have a "SetMaxArmor" function by default everyone armor cap is 100, to be able to regain your armor more then 100 you would need for it to be set using the function "SetArmor" or the ULX command, so entities such as armor batteries or armor kits wouldn't work. Therefore, there would have to be an entity made for each specific job's armor amount that sets your armor. It would be simple, but require a lot of entities to get the exact armor for every class.