We had time enough to take a shower, run downtown to Sapporo for lunch, and take the Moiwa-Yama ropeway to the top of a local ski mountain to see the sunset and Sapporo lit up at night.
The initial thinking was that we'd wake up the next day, check in all our baggage, and then take the train back to Chitose (5 minutes) for brunch. But when we went to check in everything at 9:30am, we were told that our original flight to Narita had been cancelled, and we had to take an alternate flight to Haneda airport, transfer to Narita on a bus, and then board our SFO flight from Narita. That led to us getting onto a 10:30am plane.
The whole morass went surprisingly well (perhaps not surprising, since the only person I've ever heard of who was disappointed with Switzerland's efficiency was a Japanese woman) --- we were handed envelops with cash to buy our bus tickets with, our bikes were checked and again treated with white glove treatment by ANA, and the bus transfer went well.
Once in Narita, we had plenty of time to buy lunch, look around and spend the rest of our cash. Unfortunately, between Narita and San Francisco, my Canon G9 went missing. That was very sad as I had no pictures from the last week of the trip as a result!