Japan in December with a 10 month old - should we do it?

We want to bring our 10 month old to Tokyo and Kyoto in December. We have hotels booked and I would be bringing my parents along with my husband and baby. I keep hearing how complicated it will be if anyone has realistic experience/hindsight on whether to actually go, or whether to cancel. This will be my 4th Japan trip as it’s my favorite place in the world. Baby will be on formula, he’s quite temperamental but I am wondering a few things:

1. Do you take them back to hotel for a mid day nap, or have them sleep in stroller on the go?
2. Are they just in stroller / carrier all day walking around - if so, won’t they lose out on exercises like tummy/crawl time and then be less sleepy?
3. How long will it take for baby to adjust to time zone change?
4. Did you stay home for dinner while baby slept, or did you hire a hotel nanny/is there a service?
5. I’ve been in December, which is cold, but did you bundle up baby extra warm/how to tell if they’re too cold/hot?
6. Were subways or taxis easier (I’m bringing the Doona)?
7. How did you manage formula / water / bottles on the go?

Overall, is it worth going? Or will baby just be very uncomfortable and we will all be annoyed vs enjoying ourselves? Thanks in advance!