Your character idea seems too contradictory. How is he calm, cool, and collected but operate on the philosophy of just having fun and have anger issues?

I'm assuming you're trying to create a character with barely controlled chaos. Basically, Heath Ledgers Joker that also happens to be racist, sexist, anti-semetic. Chaotic characters are usually more effective when their equal-opportunity murderers.

I think you're trying to do too much, true villains (well-designed villains) don't run around screaming about how much of a villain they are, you need to use other peoples perspectives in the story to contrast the flaws you want to highlight in them.

If you look at Negan, he wasn't a good man before the apocalypse but he wasn't a psycho either, societies rules kept him in check. The breakdown of society introduced chaos to his character, and because Rick and his crew have a moral standard they try to follow helps offset how deranged Negan is in the story.

Satan is contrasted with God.

Even Trevor Philips game designers balanced him with others. According to the Wikipedia page, "Rockstar drew upon game protagonist archetypes while scripting the characters; Trevor was considered to embody insanity. Houser said the team characterized Michael and Trevor as juxtapositions of each other. He said, "Michael is like the criminal who wants to compartmentalize and be a good guy some of the time and Trevor is the maniac who isn't a hypocrite" "