Hey, I was just talking about how my mother used to own a VESPA when she was in college! So 1A: Italian scooter brand was a gimme, and a quick entry into the puzzle. I'll give it a B+ for a cool word and the nostalgia.
So my error was silly. I put in ARArAT for 54D: 1994 Peace co-Nobelist (ARAFAT). I recognized something was wrong when I finished 65A: even before I put in the last A in TARE. But I didn't figure it out until afterwards, so there's your error.
This is a pretty darn good theme, actually. I like that we get two 16-letter answers in this 16x15 size grid. It's refreshing to get the entire OTOLARYNGOLOGIST instead of your typical ENT. And 51A: Hard rubber, maybe (MASSAGETHERAPIST) is a quality clue and answer. So the revealer is even better with its silly pun (WIZARDOFAAHS). I don't love PYROTECHNIST, putting it in with a wince even as I knew it had to be correct. But that's a small price to pay.
During solving, the fill felt smooth overall. ILLUMINATI is a good entry, although the clue is overly verbose. OPENSDOORS is not great. I liked ATTICA and MYRTLE. And EDAM is always a happy image. 9D: Risky way to buy a used car (ASIS) is a new and clever way to clue that bit of crosswordese.
Of course, now I look more closely, the more I find that I didn't like. Maybe we shouldn't be parsing these puzzles so closely? On the other hand, what then is the point of this blog?
Anyway, I'm just going to note that ITERS should be "itinera" and leave it at that.