>I wonder if his books would have been as good if PKD hadn't been so fucked up as a person

I can't even see how most of them would've existed to be honest. Most of P.K. Dick's work is about his mental issues in particular in combination with the psychedelic culture he was surrounded by. Always loved the attribution in A Scanner Darkly:

https://www.goodreads.com/quotes/8446272-this-has-been-a-nov...