As it is, we can all agree that the loot system is far too arbitrary. I think if you do something awesome, there should be an increased chance (albeit small) of getting a good item/engram. I don't mean a headshot should yield a legendary auto-rifle. I'm talking about rare instances, where you find yourself briefly performing like a god. Instances that not every player will pull off. For example:
Eight or more enemies killed with one nova blast -- 15% chance of a blue/legendary drop.
Five consecutive headshots within five seconds -- 10% chance.
Two different enemies melee-killed while in mid-air -- 15% chance.
X amount of enemies killed within a certain amount of time -- 10% chance.
100 percent accuracy over at least 100 rounds within 10 seconds -- 5% chance.
These context-sensitive reward chances could even come as skills attached to weapons. ie: Scout rifle with the unlockable, "a precision shot with every round in a magazine within 20 seconds yields a 20% chance of legendary drop." Or on a machine gun, "Within 20 seconds, hitting an enemy with every round for three consecutive magazines yields a 5% chance of legendary drop."
Think of the gameplay depth these context-sensitive tweaks could offer! Obviously, the specifics could be balanced by those who know more than I, but I think if you do something awesome, your chances of getting something awesome should increase. Thoughts? Ideas? Beheadings?