Simplistic writing deals with simplistic characters. In general, such people are absolutes. Characters are absolute good or absolute evil. If a character is bad, then they are also wrong in their beliefs. More importantly, they are wrong in all of their beliefs.
Although such stories and characters do have their place, I am not interested in them much. I care about characters who are imperfect, who are not absolute. I want characters who are wrong, but not all wrong. They are so difficult to handle.
A character who volunteers at a homeless shelter is a good person, but if he also beats his girlfriend, we will have great trouble liking this person. Imagine he is also a spiteful racist. We would eventually start to think that everything this guy did was horrible. But despite all of the awful things he does, his volunteering is a good thing; it cannot be argued.
Consider characters as people. I have met very few people who would count as being pure evil. No matter how hardened a bastard they are, everybody does something heartwarming eventually. How would seeing such conflicted characters affect your stories?