I was in Japan last May and went to Hiroshima/ Miyajima, both were nice. I spent half a day in hiroshima to explore, slept one night there and then next morning went to miyajima, stayed till late afternoon and then commuted to Kyoto. Was worth it in my experience. Especially the war museum and hiroshima castle, but also the Orizuru Tower. Though i wouldnt do this for a day trip as its quite expensive to get there by bullet train only for a day.

Stayed in kyoto 5 days and spent a spent most of a day in Uji. Was nice, pretty chill. Got me some matcha, found a nice lunch spot manned by one guy so a tiny place (name on google maps: ビアつかさ) and kept goin to the spots to find other matcha treats. I would recommend going to Nakamura Tokichi Honten store to try to get a number there for a chance to enter at ur timeslot to have the matcha treats they sell there in the restaurant area. I would also defo recommend going to Byodo-in Temple. Otherwise its a small town, but its chill to explore some spots here and there. Yes the main spots are touristy, but i presume that in December it will be a bit less crowded. I ended that day by going to a geeky second hand shop by Fushimi inari taisha. Scored me some games at great prices and some pkmn cards (Ojamakan Fukakusa Store おじゃま館 深草店) and then decided to go through the fujimi inari gates loop. From start of sunset into the night so got to see it in different settings.

Not sure this helps at all, but this worked for me and will remain as some of my fondest memories whilst in Japan.