Magic and Rare items only dropped off Champion packs?
Legendaries only came from bosses?
Treasure Goblins and Resplendent Chests were subject to RNG and could drop anything?
What if in order to get the better loot to drop from each grade of monster you had to kill x amount of lesser quality monsters to increase your chance of that better drop?
Example: In order to increase the chance of a Rare drop from a Champion pack you first have to kill 100 white enemies. In order to increase your chance of a Legendary drop from a Boss you first have to kill 100 white enemies and 10 Champion packs.