Help with itinerary - 4 weeks in november

Hi guys,

I am slowly putting together my itinerary of 4 weeks in japan. While I know where I want to go, I need help in knowing how many days I should spend in each place? Any help is appreciated!

- Tokyo: 1 week

- Kyoto: 1 week

- Kasuga-taisha
- Nara Park
- Arashiyama
- Kumano Kodo

- Kanazawa
- Takayama
- Magome
- Tsumago-juku
- Kiso
- Nagoya
- Kenroku-en
- Noto peninsula
- Nakasendo Highway
- Shirakawa-go
- Gokayama

Nice selection of places for a 4-week visit!

Assuming you are both coming to/going from Tokyo (either Narita or Haneda), I'd suggest splitting the 1 week of Tokyo into half at the beginning and half at the end.

It could be rather chilly, especially at Takayama, Magome, Tsumago, Kiso, Nakasendo, and Shirakawa, so factor that into your plans and your clothing. And if you're in that region, consider adding at least a day in Matsumoto to visit the castle and other interesting sites in town. And if you have the time, take in the fantastic onsen options, either in Matsumoto or in the surrounding areas. In Matsumoto, there's the historic Biwa-no-yu for starters, and here's a representative link for something good that isn't far from Matsumoto:
https://www.youtube.com/watch?v=-iRaYnF9WpQ

Magome and Tsumago: Both very nice places! But visiting both could be overkill unless you plan to make the walk, which, once again, could be cold. Dress accordingly.

Adding to the above comment, - Shirakawa-go & Gokayama is possibly another unnecessary double-up. If you wanted variety I would suggest Shirakawa-go and Hidamura in Takayama, but really one would be enough.
As an observation, looking at the list of places you have, be aware that the Kumano Kodo are quite hard.

The Kumano Kodo is beautiful, but most sections are not made for the casual hiker. A good level of fitness and proper preparation in equipment and the like is needed. I hiked for one day proper (plus other shorter sections) and found that I was moving less in distance terms than almost any location I normally visit in Japan (I'm more of a light hiker though....)

https://www.japan-guide.com/community/mfedley/report-2248
https://www.japan-guide.com/community/mfedley/report-2251
https://www.japan-guide.com/community/mfedley/report-2254
https://www.japan-guide.com/community/mfedley/report-2256

What airport(s) can you fly into and fly out from?

You seem to have picked up your destinations from plural sources.

"Kiso" here sounds a little vague
because it is originally a name of a former province.
So is "Noto"; I wonder what sites in Noto Peninsula you now think about.

Some of the listed places geographically overlap.
: Kasuga Taisha Shrine is in Nara Park.
: Arashiyama is a part of Kyoto City.
: Kenrokuen Garden is in Kanazawa City.
: Tsumago and Magome are post towns on the Kiso road [Kiso-ji],
which is a section of the former Nakansendo highway in the Edo Period.

Generally November is a good tourist season in Japan,
thanks to the autumnal foliage and the tendency toward pleasant weathers.

In November 2018,
the three days from the 23rd (holiday) to the 25th (Sunday)
can be busy tourist days,
when some popular sightseeing spots may be crowded.

It sounds better to leave your itinerary flexible,
with some days to have a rest.