; h e a d c a n o n
If you ask him, he'll deny preferring either, but truth be told, he likes Moriarty more than he likes CAM.
John realizes that Moriarty is completely insane. And he's terrified of Moriarty, in an odd way. He doesn't miss him, he wants Jim out of his life.
But Magnussen? He makes John angry. There's no reason beside profit for what he does, and it pisses John off. It makes him angry that he's allowed to keep this up, it makes him angry how much power he has over people, and God does it make him angry that he flicked John's face.
What Magnussen does is just 'look how useless you are, look how I can control you for my own purposes'. And John sees that in Jim too, but not in the same way.
The power Jim has is a completely different one. It's danger, and madness, and perhaps a little power. but he's in it for the same reason Sherlock is in the game, and really, the same reason John is, to a lesser extent—-
Because normal life is boring, and the cases, in Sherlock and John's cases, and the jobs in Moriarty's case are just a way to make it more interesting, keep them from going mad.
CAM is exactly what he says he is. A businessman, and what he does, he does for profit, and power, and John despises that.
