Just a little thing that might help.
My idea is a button you would press (toggle or hold) which would allow you to pick up any weapon of the floor while running. i.e a friend shoots a guard and you, the POW runs, holds down the key, does a really quick animation and picks up the gun with its single mag. This would be an alternative to running up to the gun, looking strait at it, scrolling, selecting pick up "ABC" and then looking back up to see that the short opportunity has gone and your now facing the rest of the guards who have now focused on you.
Im not quite sure if weapons that belonged to someone who died still contains the magazine.