There's also a Hilton, Crowne Plaza, and several other hotels in and around Narita.
How early is your connecting flight?
I'm doing an overnight at NRT next week also, arriving around 3pm on AA connecting on JL down to SIN the next day around 10am. I've done this several times, it's plenty of time to go into the city and have a nice night in Tokyo before heading back to NRT the next morning.