I think I might have found something that can be considered an exploit, i.e using a game mechanic to gain an advantage.

So, in Outpost you can grab weapons off the ground and then at the end of the wave, you can head to the supply crate and grab ammo for that weapon. I extrapolated this out, and found a way you can essentially double your supply points.

Since for each class you can create predefined loadouts, I was able to create 2 loadout sets, one set for primary weapon and another set for armor/secondary, each using the full allocation of supply points (2 points per loadout at wave 1, 4 points at wave 2, 6 at wave 3 etc). Now, because you can do that per loadout, you can effectively double that, becoming 8 points at wave 2, 12 at wave 3, etc.
So, what you do is, equip the primary loadout, find a weapon on the ground, switch it out for your upgraded primary, resupply on your secondary/armor loadout, pick up your upgraded primary off the ground, return to the supply crate to load up on ammo for your primary. (see this video for a demo).

NWI has tried to nerf this exploit by restricting weapon pick up, but the weapon restriction only kicks in if you click on "Save Loadout", not if you click "Resupply". Also, if another player picks up a weapon that is restricted for you and then puts it down again, the restriction is removed. <-- Possible bug?