To me, loot drops shouldn't be things that happen in every skirmish. I think they should be rewards for overcoming something a little more challenging (think Rixis and the Spider Tank from the E3 demo). I would assume enemies would drop some kind of ammo after being killed, but I don't want to have to check my inventory every time I drop a Dreg to delete a common hand cannon that I will never use, like what ended up happening in Mass Effect 1. I also don't want to have even the slightest chance of picking up an exotic from putting down a Vex Goblin. I want to feel like everything I have was earned, not given to me by some quirk in the machine