We didn't get into his attitude toward women when I interviewed him for Down Beat back in 1968 or '69. But he was on a personal level as mean as a snake, even rather cruel (though I admit that in my still callow relative youthfulness and anxiety to please I left him an opening or two that I shouldn't have). The interview took place by a motel swimming pool with most of the Mothers within earshot, and they (Don Shelton, especially) were more or less appalled at the way Zappa had behaved and gathered around after he'd left to say a good many insightful things about the band that helped to make the experience a success after all, at least journalistically.
I used to work with a drummer who went on tour with Zappa as a percussionist, and he said that FZ treated the musicians like dogs.
And then there's his two famous quotes about jazz:
"Jazz, the music of unemployment".
"Jazz isn't dead, it just smells funny..."
Well, that was a dumb forecast if ever there was one, jazz is still here and..you know the rest.
I've listened to a fair amount of Zappa and the sky-high praise for him always had me a bit puzzled, a lot of his output seems to oscillate between juvenilia and academia.
I agree completely with your assessment of Zappa.