I really dislike william afton not for the things he did (killing kids, being practically immortal, etc) but for the things he DIDN'T do. you were just given the opportunity to understand and analyze the human soul to a degree beyond scientific comprehension and all you do is make even more problems for yourself and your most hated spawn you call a child???
Even if he didn't use it for good, he didn't try to do ANYTHING interesting like put me in his shoes and you will see me do things even the cia wouldn't. He didn't even try to test how recently a body needed to be in contact with the animatronic to possess it or how many souls you could pack into one amalgamation of an animatronic or at least check how decommissioned an animatronic could be and still be functionally living (technically springtrap himself is an example but he's also the victim sooo L)
its just disappointing to see how such a good way to check how the human soul works is given to the person with the least amount of curiosity besides bringing his dead son (which he killed due to his stupidity) back to life unsuccessfully