Thanks for the suggestion Hydebear. Newport looks like it's well worth a visit.
My parents went to Cape Cod about 10 years ago and highly recommended it so it'll be on our list of places to visit if we hire a car.
I will make sure when I get my next 2-4-1 voucher that I book early enough to get to go somewhere further to enjoy First for longer. Tokyo or SFO it'll be.