I just watched "Zugzwang" for the first time... Diane x Maeve's storyline didn't really land the way I expected it to. I wanted a Foyet-level capability and motive.
Incoming rant. Spencer Reid fans, do not attack me. I love the show.
Diane's motives were shallow. I don't think she can outsmart a geneticist with a BAU Agent boyfriend for that long. See.. I always, ALWAYS try to understand where the UnSub is coming from even if I don't agree with them. Obviously, I don't agree with murder. But I would ask myself if I would do that, too. Most of the time, my answer would be, if I were as crazy as them, I would. However, Diane is just out of reach for me. And it felt like the entire point of that episode is to make Reid suffer. There are worse ways to make Reid suffer.
For instance, Reid could've found Maeve already tortured and unrecognizable. Meaning, if Maeve died and he buried her, he doesn't have a "good memory" of her face. He cannot romanticize her death. That'd be a great way to weaponize his eidetic memory. If the first image he sees of her is all covered in blood, those headaches will now be mixed with nightmares (as in screaming in the middle of the night type). That's going to hurt more. He can contemplate relapsing to his addiction, too.
Also, I'd increase the credentials of Maeve's stalker. Maybe a professor disgraced because of Maeve's genius or a head of a national project whose funds were deprioritized because of her. Then, that would be understandable.