Yeah, I guess you're right about Throbbing Gristle - to be honest, I don't know much about industrial music generally.
"Synthpop" is a tricky term because it runs the gamut from very experimental stuff (e.g. early Human League) to very poppy stuff (e.g. later Human League). Art Of Noise are kind of a spinoff of the former, with a sampling angle (why I lumped it in with the Byrne/Eno album) - I mentioned them in part because I was flipping through that Reynolds book and they have a decent section (alongside Frankie Goes To Hollywood and other stuff on the ZTT label. I guess "new pop" is a term that's sometimes thrown around for this kind of stuff.
Anyway, I probably wouldn't put Art Of Noise on your list, but they're fun regardless: this song is pretty representative. (Fun video too)