These are the sort of things I like messing about with in my fanfiction. You start with the idea that most of the so-called 'evil' people don't think of themselves as 'evil'. That most of them honestly believe that they are doing the right thing, the best thing.

That's why I made Dumbledore a HYDRA agent and added the Green Wizard Dalek to the New Dalek Paradigm. That's why I put a Gou'aould symbiote into Salazar Slytherin and made Dracula an ally of Harry Potter.