Where to stop between Hiroshima and Hakone

We are doing a route that requires us to go from Hiroshima back to Hakone and then to Tokyo. We have already been to Kyoto before going on to Naoshima and Hiroshima.
I have one day to play with between Hiroshima and Hakone, considering stopping Osaka or Nagoya to break up the journey. Love some ideas

If your one day is a whole day (without any travelling from Hiroshima), then I would recommend staying in Nagoya. From Nagoya you could look at doing a day trip to Takayama or Ise Shima.


Takayama
https://www.japan-guide.com/e/e5900.html
https://www.japan-guide.com/e/e5908.html?aFROM=2155_5900

Ise Shima
https://www.japan-guide.com/e/e4310.html
https://www.japan-guide.com/e/e4304.html?aFROM=2155_4301

Also consider Hikone (the shinkansen stop is Maibara). Pretty castle town with nice views over Lake Biwa.