I am thoroughly fed up with psycho serial killers as a plot device.

[scarletwoman]

2. Thank you. I think the psycho serial killer trope is a cop-out. (so to speak)

You don't have to base it in any kind of reality, you don't have to explore real people and complex relationships, you just make up some totally insane evil-doer with no motive beyond being psycho. It's not that different from fundamentalist religion, where evil is projected onto some kind external supernatural entity, instead of the recognition that all humans have the capacity to engage in "evil" behavior - nothing supernatural about it.

I have stopped reading many crime novels because I begin to feel as if the world is full of psychopaths.

Exactly!