I have an overnight 23 hour layover on my way home from SEA in December and have booked the IC Yokohama Grand as the rates were less than half of what even the Hilton Odaiba (the cheapest Hilton property) wanted. Hopefully the Hilton Yokohama will have similar rates as the IC.

Yokohama is a nice place for a day, you could visit Kamakura from there more conveniently. I visited there over 10 years ago and stayed at the IC Yokohama Grand for a couple of nights. But for a first timer visit to Japan it depends how long you are visiting, a usual first time visit would want Tokyo and Kyoto at the top of the list, Yokohama would be lower on the list and there are many other places I would prioritize over it - Hiroshima, Osaka, Nagasaki, Sapporo, just to start, it also depends on the time of year and when in November.

If I only had a week in Tokyo The five lakes/Fuji and Nikko day trips would take precedence over Yokohama.