My family (4 adults) will be in Hokkaido in December. We will be driving. We intend to rent a car at the airport on the arrival and return in Sapporo. (4 days rental) Our itinerary is as follows:
Dec 15-17 - Shin Chitose Airport to Noribetsu/Lake Toya
Dec 17-19 - Niseki (just to have fun with the snow)
Dec 19-21 - Sapporo /Otaru
We intend to drive as the timing will be flexible. Appreciate it you could comment on the itinerary.