SO, all in all I think that even if it ISN't KQ I am increasingly excited by the idea that it would have been
someone LIKE HIM. That seems to put it on firmer ground and certainly the methodology of putting him on the suspect list was sound, and not based on wild speculation. Inevitably speculation HAS to enter into the picture somewhere if you set your spotlight on a certain guy. I am not seeing anything on KQ in terms of connection with the other cases, its just a Stine proximity, but the type of man he is- an innovator, millionaire, etc., broadens the field and gets it out of the doldrums. Z wasn't a nobody trying to be a somebody. He already WAS a somebody- in some way. Which can only make it easier to find him. If he were just some pathetic wanderer we wouldn't know who he is. There are a hell of a lot fewer KQs in the world than garden-variety lowlife-rapist types.
Then again, think of Gacy. Gacy met
the first lady. Lawd, wrap your head around that. He also had a bunch of KFC restaurants. (Chicken= young boys

)
So Z might be more like Gacy, in terms of being able to hang in the real world yet be a murderous perv in his free time. Not many of those guys are terribly well adjusted but Gacy and Bundy seemed fairly stable- for a time anyway. They had homes and jobs and people liked them, sort of. Whereas other dudes were heavy-lifting-but-stable types (Leonard Lake, Kenneth Bianchi, Israel Keyes), or creepy obviously-damaged guys like Ramirez, Arthur Shawcross, Dahmer.
These are obviously my own ad-hoc categories here but I think its very important to look at the overall match on the personality type and flesh out from there. I think Walter was right when he said that Mike had it- may not be THE guy but its a guy LIKE him.