Brave Mom & oma visit son and tour

My Mother and I are visiting Japan over Christmas. I am wondering if our itinerary is feasible and would like to know is we have included and/or forgotten anything that we may regret as this will probably be our only adventure in Japan.
Arrive Dec 21 17:00 Osaka,my son is joining us. Staying in Osaka 21,22,23. Hope to see Osaka Castle, aquarium, Umeda Sky bldg, Mizudera/Shitennji, Spa world maybe? Kui-Daore area, Universal studios(his choice :)
Dec 24 Travel to Mount Koya stay at Shojoshin-in Temple
Dec 25 Travel to Nara visit then continue on to Kyoto, that evening Pontocho Alley
Dec 25, 26, 27 Kyoto visit Kiyomieu Temple, Gion district, dress as Maiko/Geiko what is the difference? day trip to Arashiyama on the 27 th?
Dec 28 train to Himeji Castle then on to Hiroshima visit late afternoon/evening spend night
Dec 29 Miyajama Island then return to Tokushima where my son lives.
We do not leave until Jan 2 18:40 and had wanted to stay at an onsen in the Iya Valley however all is booked because of holidays. Am looking for something to do those last few days. I have looked at train fares for all our trips and compared them with the JR pass, according to my calculations the pass does not save us any money. Is this right or am I reading the prices wrong and forgetting something? Thank you for any advice you may have for two adventurous ''old souls''

Your trip looks intriguing, but you may be pushing things time-wise. It always takes longer than you think to get from here to there - not the actual transport but getting to the station, waiting for the trains and then getting to your final destination. I'd advise going back over your itinerary rather critically and deciding whether its doable. Being a senior myself, we found it good to leave some breathing space!
With respect to getting dressed up as a maiko or geiko, I'd guess that it would be quicker to dress as a geiko - their garb is a bit simpler, and I don't think they use the white make-up as a maiko does.

Hi Carol,
Looks like you are spending a lot of time in Kansai area. I agree JR pass would not be a good idea. I recommend Kansai thru pass.