One of the quirks of my fiction so far is that I've deliberately avoided writing villains. For one, I'm trying to world-build a place where aggression and banditry of all sorts are rare. For two, I find situations of man vs. nature or man vs. himself much more interesting, personally. I love writing about intelligent people faced with a difficult problem figuring out how to overcome and succeed, and I felt like those sorts of situations were better ways to introduce and develop characters, rather than having some obvious evil for them to rail against.