Here is a London analogy:

You're taking a train from Plymouth (Hiroshima) which will miraculously deliver you all the way to Liverpool Street station (Tokyo Stn)... and.you have a flight from Stansted (NRT) the next day... and your points could be used at a hotel 15 mins walk from Paddington (CH), a hotel near Baker St. (Crowne) or a hotel in a somewhat awkward corner of the docklands (IC) which can be reached by train with a couple of complicated changes - but is probably best approached by taxi.

If I were travelling with no luggage and I was desperate to save money I might stay at one of those places (prolly IC)... and suffer the additional transportation hassles.

But otherwise, I would be inclined to pay money for a hotel in a convenient place - Tokyo station area or Nippori or Narita.

Tokyo station has hotels nearby - but it's a premium price area. THe Marunouchi Hotel is (IMHO) a good enough level of comfort, unsurpassable convenience and OK pricing at about 21000yen for singles. At half that price you can stay at the business hotels on the Nihonbashi side or Yaesu side of the station. For better value options stay near Nippori station (and take the keisei line from Nippori next day) or stay in Narita City.

Alternatively, stay an extra night in Hiroshima and take the 07.55am flight to NRT.