I always went for what I thought would be the most funny. Pretty much just play for fun, and that's what you'll have. I will say this.. If you want to be bad, you have to pick your companion for that. Some REALLY don't like when you're mean/cruel/deranged. Others will laugh with you as you light someone on fire just so you can roast some marshmallows.
"I would rather be exposed to the inconveniences attending too much liberty than to those attending too small a degree of it." Thomas Jefferson