You act like you expect me to run through all of cinematic history or something.
Having a guy who was originally portrayed with some benevolence, only to later give him the qualities of a villain is hardly new in any media. Recently, you could look at Doc Ock or Sandman in the movies. Trying to separate it into degrees, claiming 'this guy wasn't as clean-cut as this one' doesn't really change it. It's still the same deal and stands out as unoriginal and lazy.
Beyond that turning Richard villain undercuts a good deal of what Richard represented in the first film. If he's truly all 'boy scout', he'd find another way of dealing with adverse circumstances than becoming evil. As much as a favorable response as Richard received in SR, do you really think people want to root against him?
That possibility is part of why I don't like this Supes/Lois/Richard triangle that's been created. With Jason biologically linked to Lois and Superman, I'm struggling to see a way to resolve this without it getting ugly (or resorting to someone's death). It's just a messy situation.