Itinerary check for 20 day trip

Hi,

I'd greatly appreciate any feedback on my proposed itinerary and any changes you think would improve it based on ease of travel between stops.

Day 1-3: Tokyo (3 nights stay
Day 4: Hakone (1 nights stay)
Day 5-7: Kyoto (3 nights stay)
Day 8: Nara (1 nights stay)
Day 9: Koyasan (1 nights stay)
Day 10-11: Osaka (2 nights stay)
Day 12: Naoshima visiting Himeji on the way (1 nights stay)
Day 13-14: Hiroshima including a trip to Miyajima (2 nights stay)
Day 15: Kanazawa (1 nights stay)
Day 16-17: Shibu-Onsen including a trip to see the snow monkeys (2 nights stay)
Day 18-20: Tokyo and an very early flight back on Day 20 (2 nights stay)

I would also appreciate advice on the best pass to purchase for this trip. It covers all the places we would like to visit but we are happy to do them in any order.

Thank you in advance.