Are these days too packed?

Am I doing too much on these days?

Day A
Shimokitazawa
Jiyugaoka
Hiroo
Tsukishima
Christmas illuminations in Roppongi

Day B
Tsukiji outer market
nezu shrine
Yanaka ginza
Kagurazaka
Akihabara Electric Town (we are not so much Otaku but may just go to check it out at night? head to an arcade etc..)

Day C
Yokohoma
Cup noodle museum
Shin Ramen Museum
Red Brick Xmas Market
Shinjuku Kabukicicho

Depends how fast you move and how much you plan to see, but yes they're pretty packed. Day A is of particular concern because shops rarely open before 10am so you're off to a late start by default. You might have more luck going to Kabukicho on Day A since you'll be on that side of Tokyo already. Move Tsukishima and Roppongi to one of the other days.

My two cents:
Day A
Shimokitazawa
Jiyugaoka
Hiroo
Shinjuku Kabukicicho

Day B
Tsukiji outer market
nezu shrine
Yanaka ginza
Kagurazaka
Tsukishima
Akihabara

Day C
YokohAma
Cup noodle museum
Shin Ramen Museum
Red Brick Xmas Market
Christmas illuminations in Roppongi (though I think there's enough other illuminations without having to go specifically to Roppongi, such as Odaiba after Tsukishima on Day B)
https://www.japan-guide.com/e/e2303.html

It's slightly annoying to get to and might not be of interest to you, but Sankein Gardens in Yokohama are the best gardens in the Kanto Region. If visiting in early December, there might be some autumn colors left....

https://www.japan-guide.com/community/mfedley/report-960

Move Tsukishima and Roppongi to one of the other days.

Have you even been to Tokyo? It literally takes THREE MINUTES to get from Hiroo to Roppongi (on the Hibiya subway); why would you move it to another day? Just go to Roppongi immediately after Hiroo (via the Hibiya line), then from Roppongi it takes 15 minutes to get to Tsukishima on the Oedo line.

To the OP - I'd suggest looking at Google Maps, and grouping locations that are close to each other, or at least on the same train line, together. You can simply plug in two points on the map and it will tell you how long it will take to get from one to the other, and how many different trains, often with several alternate routes.

For example, Shin-Yokohama Ramen Museum is near Shin-Yokohama station, which is a bit removed from your other Yokohama destinations, so I would do that one either first or last.

Also, consider what times of day things are most interesting. For example Akihabara has a lot more going on during the day, and I think most of the shops close around 8pm. Hiroo is pretty boring all day and night, but I assume you have some specific reason to visit there. Tsukiji Outer Market is a good early-morning stop (as you have it) for when everything else is still closed. Temples and museums also open early than shops.

All in all it's not too much, but I would organize it a bit better in terms of transportation.

@ "DEAREST. Of course I've been. Lots of times in fact. It was more in reference to the fact that Shinjuku is right there. You don't have to be a rude cow, FFS.

Thank you, I appreciate all the input here.

Would there be enough time to go to the garden in Yokohama?

Perhaps I will skip Hiroo if it is boring. I saw an article that said it was a good place for food lovers but i will be enjoying good food anyway on the trip i am sure.

If i go to Odaiba Mori Digital Art Museum one of these days would that be feasible? Reading reviews people recommend going in the morning.. Would i have to swap it with something else on the itinerary such as Akihabara?

How long would it take to walk through Yanaka Ginza (with stops for food). According to google maps the walk to Nezu shrine doesn't seem far, is this correct?

You should be able to fit in Sankeien if you are not too slow. Shoehorn it in if you have to - it really is an amazing place.

Yanaka Ginza can take 10 minutes - 30 minutes if you walk really slowly. It is pretty small. If you are shopping/snacking it can take longer. First person I took there really wanted to go and after walking through commented "is that it?" They were underwhelmed.

I was curious to see Hiroo on the list. I visit the area reasonably often because my lawyers are based there, but I wouldn't consider ever including it as a tourist stop. It is a nice (well to do) neighbourhood and I've eaten at a few places because of timing (lunch), but nothing I would consider special. Ebisu (next door) would be a better option with Yebisu Garden Place and some of the spots around Meguro would be more interesting IMO.

Ah, I assumed that you had a specific reason for Hiroo. There's going to be good food everywhere you go, and Hiroo doesn't really stand out in that regard. (Although for foreigners who live here, it's notable for its international supermarket.) If you're willing to consider substitutions, I'd say that Naka-Meguro and adjacent Daikanyama are much more interesting to stroll through than Hiroo. Jiyugaoka is cute, but it's mostly just filled with housewares shops.

I just went to the Teamlab Borderless exhibition last week (aka Mori Building Digital Art Museum), and it was really a unique experience. You have to buy tickets in advance, and they limit the number of people who can enter at any given time, so it doesn't get too crowded. Starting at around 3:30pm on a weekday we only had to wait around five minutes, but when we emerged at around 5 or 5:30pm there was a much bigger crowd at the entrance. Perhaps mornings are even less crowded, but I'd say anytime before mid-afternoon is probably not bad in terms of waiting time. (Although some of the fervor may have died down by the time you get here.)