More consistent sleep probably wouldn't hurt XP I know I definitely need more (I can feel it affecting things), but I am still failing so far (I think it will get better if I can work this schedule out, but that requires me not getting distracted).
Spending all of your time trying to maintain "healthy" is counterproductively unhealthy though, obsessions seem to be generally unhealthy and that's what that is.
I'm very limited for comment on the vampire example as it's been a very long time since I've gotten to read books, but that type of example is stuff I've generally only found in tabletop roleplaying. All the vampire books I'm aware of have basically been romance or monsters or romantic monsters (maybe the people inclined to write about that stuff are about as limited in imagination as I am on comment where that's concerned, or perhaps the ones that deviate from those tropes aren't well received by people who insist that they want new and interesting while only accepting what they're familiar with and rejecting the things they insist they want?).
Definitely not! :D
I know a few people like this where a lot of their productive time is spent making themselves feel as good as they can physically, but they end up "overinvesting" and skipping other aspects of life, so they don't feel that great and then end up in a loop.
No idea about the vampire writers, but I think "villains" are often representations of ourselves and our fears - our darker side. The way we might be, if no one was watching.