I ended up doing the ride with the Challenge Strada Bianca TLR 36mm tubeless tires aired to 50/52psi. The pre-ride description of road conditions was probably milder than what we encountered. There was a LOT of heavily cratered asphalt and sketchy road surface. The Strada Biancas were the perfect choice. They were fast on smooth pavement and confidence-inspiring everywhere else. Good ride. It was a good all-around test and they passed with flying colors.
The ONLY bad thing about the Strada Biancas is that, no matter what you do to stop it, they seep a little air (but no sealant) from one day to the next. I generally expect to lose 10 psi in 24 hours. That's not a big deal, though. I just air up my tires before I ride. Problem solved.