Who said anything about the player character? What part of "******* who flushes the rulebook dwn the toilet" implies insanity, to you? There are degrees of *******, and people never act until provoked so the odds of deliberately harming children and homeless are very slim. Even Lannister has an understandable logic for the things he did as cruel and as fucked up as it was. People insult them, they get punished, people bore him they get punished, he thinks someone looks homosexual they get a crossbow through the groin.
But I got a think the simplest and one of the most accepted definitions of chaotic evil might be, the one I probably should have started the OP with: bully.
The typical bully is a classic example of chaotic evil, characters like Tuco or Joffrey are really just cowards at heart. They don't follow rules until they're cornered.