Cold is great. He just loves being a badguy and completely hams it up. If you watch The Flash, in his first appearance he isn't actually super hammy. He's just a jewel thief. Then he gets the cold gun and realizes he can be a "Super" Villain and goes all in on it. He intentionally hams it up to play the part, even with lines like "you should have known, I'm a badguy". He's an actor playing a character playing a character. It's pretty good once you realize that. He just loves being bad, loves saying the puns, loves punking Flash. Even in this show already his main goal is to steal shit throughout time. He just loves being bad. He's not guy who wants the world to end, he just wants to enjoy himself.