Villains that were way more interesting than the hero
A story is greatly improved by having a big baddie that's intimidating, mysterious, cruel and frighteningly determined...some or all of these qualities NEED to be part of the villain's character to make a good story work
Consider Inglorious Basterds...Instead of being an evil, murderous monster excited by his work Hans Landa is a pudgy low level Nazi Party functionary too lazy to be bothered
He sees Shosanna flee across the field in the opening act, shrugs and thinks 'Meh, I'll just head off to Paris to eat fancy French Food and flirt with Fancy French babes...'
That does not work
Let's chat about villains so perfectly written and performed that they were way more watchable than the hero