This is quality work. With amazing detail, simple way to use it, and good sound.
I have some suggestions for a follow up:
-Possibly upgraades, like extended clips, silencers, and style upgrades (like a pimped look in army of two) that's bought through exchanging shots fired for the upgrades.
-different weapons, like a mini-uzi, scorpion, etc.
-I'd suggest keeping to smaller weapons because assault rifles always look weird for these types of 'games'
Hope this helps.
Thank you for an amazing submission.