My 21-day trip. Any opinions?

So here's my itinerary. Comments, criticism, feedback are welcome.

Feb 8: Arrive Japan in late afternoon, sleep in Tokyo.

Feb 9-10: Kyoto with possible day trip to Nara. Is that too much?

Feb 11: Visit and spend night friend's home in Atami-city in Shizouka Prefecture

Feb 12: UNSURE, maybe take a day trip from Atami. Please offer suggestions

Feb 13-15: Shinjuku/Tokyo. Attending concerts on 14, 15 in Saitama

Feb 16-17: Osaka
Feb 18-19: Nagoya
Feb 20-22: Fukuoka
Feb 23-25: Sendai/Matsushima

Feb 26-27: Tokyo with day trip to Nikko. I'm open to suggestions on this one.

Feb 28-Mar 2: Disneyland, Fly back home to Canada

many thanks,

Marlene

You travel back and forth between eastern and western Japan that is not efficient.

Assuming that you need to be in Atami on the given day, I recommend the following route:

Tokyo - Sendai/Matsushima - Atami - Tokyo - Fukuoka - Osaka - Kyoto - Tokyo

As Uji said, your itinerary has a huge amount of going backwards and forwards. I suggest you carefully examine the locations of the cities on a map to find a more efficient route.

Also, you only have a day and half allocated to Kyoto AND Nara, which are considered by many to be the best places in Japan to visit, and are not visiting Hiroshima/Miyajima, Takayama or Kanazawa, while are spending a lot of time in Nagoya, Fukuoka and Sendai, which are not known for their wealth of tourist sites.

Finally, you are in Japan during the Sapporo Snow festival, which may be worth considering.