Camargo would be a great Curtis Cup Site- Cincy is plentyof city and the club is very accessible. But I do not know if it meets all the social requirements (nor do I care). It would be a fantastic site; it is probably too small for a Walker Cup.
Prarie Dunes was the first to come to my mind, as well as Cherry Hills, for the walker Cup. Since it is contested in the fall, the southern US becomes viable, so why not Champions, or Brook Hollow?
Accessibility probably works against Crystal Downs, though it would be a great venue of either event. BTW, TD misspoke: the 1991 event was the Senior Amateur, not Open. No big deal. And yes, the greens got a little speedy, though the 11th was the only real problem. Cold weather didn't help but the golf course was fantastic.
Brookline would be another great site for either event since it is now most likely through hosting Opens. COurse qualityh and its place in history should make it a front runner.