In reality, there are very few villains who view themselves as villains. They just have a certain agenda at a certain time.
The villain is usually the most interesting part. But it has to be a smart thing. Just dumb cliche villains with a Russian accent and big muscles and a mean face, I don't know. My Russian accent isn't that great, and the muscles aren't that big and the mean face is not enough. You know what I mean? It gets very boring. Tedious stuff.
I like villains because there's something so attractive about a committed person - they have a plan, an ideology, no matter how twisted. They're motivated.
Evil is relative - and what I mean by that is that our villains are as complex, as deep and as compelling as any of our heroes. Every antagonist in the DC Universe has a unique darkness, desire and drive. And the reason for being of 'Forever Evil' is to explore that darkness.
Drama's not safe and it's not pretty and it's not kind. People expect the basic template of television drama where there might be naughty villains, but everyone ends up having a nice cup of tea. You've got to do big moral choices and show the terrible things people do in terrible situations. Drama is failing if it doesn't do that.