After spending several nights in chain hotels in California, my daughters and I were thrilled to see our room at the Grand Canyon Hotel in Williams, Arizona. The hotel is the oldest in Arizona, and it might be the most charming, as well. We stayed in the Carriage House Queen, which has a queen bed in one room and two twins beds in another. The girls loved sharing a room, and I appreciated not having two share a bed with the five-year-old for the first time all week! Each room in the hotel is uniquely decorated. Ours was a modern / rustic blend that was perfectly relaxing after a nine-hour road trip. And the proprietors, Oscar and Amy, were incredibly friendly--and willing to be flexible on their "check in by 9pm" rule for a family making a long drive from California!
We only stayed at the Grand Canyon Hotel for a night, but I think it would make a great base for exploring Williams and the South Rim for an extended time. It's about an hour away from the South Rim Visitor Center.