Is my Itinerary realistic?

So prices dropped enough for me to convince myself that it is finally time to go on the trip I've always wanted to take. From September 3-14 I will be in Japan and I've already booked a few cool things along the way.

I'd really like a little feedback on the current layout of my itinerary to see if it's too fast paced. The only thing that has to be set in stone (aside from flying in and out of Tokyo) is the trip to Okayama to see Sambomaster.

September 3 (Thursday) Fly out of DC
September 4 (Friday) Land in Tokyo, check in AirBnB.
September 5 (Saturday) Ueno Zoo and surrounding areas/park
September 6 (Sunday) Pick up tickets, explore Akihabara
September 7 (Monday) Spend my bday in Hakone sightseeing
September 8 (Tuesday) Nikko? This day is mostly undecided
September 9 (Wednesday) Kamakura, Activate JR Pass
September 10 (Thursday) Shinkansen to Hiroshima, try to catch baseball game at 18:00
September 11 (Friday) Peace park and Miyajima
September 12 (Saturday) Shinkansen to Okayama, check out Okayama Koraku-en, Sambomaster concert
September 13 (Sunday) Train to Kyoto, visit Arashiyama, Ultra Tower concert (tickets not yet purchased)
September 14 (Monday) back to Tokyo, 15:00 flight out of Narita

Is there anywhere I can store my extra bag in Tokyo before leaving for Hiroshima/Okayama/etc? I'd like to do that leg of my trip with just my backpack, so if I can leave my other bag somewhere it'd be really convenient. Any other input is much appreciated, I have fleshed out my time in Tokyo that much yet, but I'll probably stay around Shibuya or Asakusa.

Doesn't look too fast paced, and you have time to do a few other things depending on what presents itself each day.

(Baseball at Hiroshima is fun - the Carps games and crowd are entertaining - beware that you might be restricted to unreserved seats up the back of the stadium.)

Thanks, I was told on reddit that I'd be living in trains and wouldn't be able to enjoy Hiroshima in the time allotted. I've been considering dropping Kyoto to not be rushed getting back to the airport on the 14th... I'd like to be able to keep it as is if I'm not going to be stretched too thin and miss out on things I'd like to see. Maybe add another day in Hiroshima and take out Kyoto?

How accessible is Kawasaki City from Tokyo? There's a festival on Saturday the 5th I'd sort of like to see.

A few questions/comments.

September 4 (Friday) Land in Tokyo, check in AirBnB.
Where is the AirBnB in Tokyo?
After a long (14hrs) flight you want a place that's easy to get to.
(Tokyo makes DC seem like a rest home) :)

September 5 (Saturday) Ueno Zoo and surrounding areas/park
You will be disappointed with Ueno zoo. Old and not nice, like U.S. zoos. And the park is nothing to write home about. Better to spend that extra day in Kyoto.

September 6 (Sunday) Pick up tickets, explore Akihabara
What tickets? Where? You don't need a whole day in Akihabara.

On the day you travel from Tokyo to Hiroshima, what time will you set off? It takes about 4 hours from Tokyo station to Hiroshima station. If you leave in the morning (say 9 am), you'll be in Hiroshima by noon time. You can easily check out the Peace Park at the end of Hondori shopping arcade which is just a few minutes away by Hiroden (street car/tram) or bus from Hiroshima station. Seeing that the Carp game is at 1800, you have a lot of time to spare if you leave Tokyo early.

Travelling to Hakone and then Nikko on two consecutive days is a lot of travel in totally opposite directions.

Have you thought of staying a night in Hakone instead?

Also, if you are visiting Kyoto then I would probably re-think Kamakura.

Don't get me wrong, Kamakura is nice but it's like a much smaller version of Kyoto. Some people will stone me for saying this, but it might feel as though it's more of the same once you visit Kyoto.

I also agree that Ueno Zoo is nothing special. However, I do like Ueno park in general as there is quite a bit to do there and it's also nice for people watching as well.

Thanks for all the feedback everyone! Sounds like I don't have to completely drop Hiroshima off my radar like I was advised on a different forum...

I'll answer questions/concerns that came up:
I haven't booked my airbnb in Tokyo yet, but I've mostly looked at Shinjuku and Asakusa. My days in Tokyo in general are not that well planned out yet because I want to make sure of where I'll be/where I'm staying throughout the trip first. Pick up tickets is picking up my tickets to the concert at the Voyagin Shibuya office - shouldn't take up much of that day...

I do plan to set off for Hiroshima with one of the earliest possible trains, I want to have time to explore/check-in and still make the baseball game on time.

I figured those two day trips may be heavy and I may restructure/drop Nikko completely. I hadn't thought about that with Kamakura, but I am still up in the air with going to Kyoto for that short of a trip, so I guess it will all hitch on that.

Sounds like two votes against the zoo, sounds like I'll need to do more research on Tokyo activities for my time there.

Thanks again for all the feedback! I'm still a few months out, but I'm trying to at least know where I'll be each day and this is all helpful. I'd love to see Osaka, but I may save that for my next trip to Japan...

Agree about Ueno zoo. It really is nothing special. Personally, I would skip it in favour of going to Harajuku station and exploring Meji Shrine and Yoyogi Park.

If you're into anime/manga/video games, a full day to visit Akihabara is acceptable. If you're really into that sort of thing, check out Nakano Broadway. Easy to access from Akihabara on the Chuo line just a few stops past Shinjuku.

I'm going for my third trip in the fall and I always slot a full day for those areas. I might do both in the same day because I've been there before and I know the area ... enjoy!

"How accessible is Kawasaki City from Tokyo? There's a festival on Saturday the 5th I'd sort of like to see."
It depends on the which station in Kawasaki is neaest to where you're going.
It also depends on where you are leaving from.

I would not stay in Asakusa because almost every time you go someplace in Tokyo you would need to take the subway first. Shinjuku is better. It's on the JR Yamanote line that makes a loop around the main part of Tokyo - 29 stations, 60 minutes, so almost every place you will go in Tokyo will involve the Yamanote line.

The basics of accessing Kawasaki are explained here:
http://www.japan-guide.com/e/e3251.html

Thanks again everyone. Sounds like I'll space out my day trips for Tokyo a little differently, plan to stick with how I have Hiroshima, and possibly skip Arashiyama for time concerns (still not sure I want to miss this). I'll definitely stay in Shinjuku, after looking at it more closely, it seems more accessible to everything.

With the show in Okayama starting at 6 and the last train out at 10:45 is it realistic to grab the train to Osaka or Kyoto and not spend the night in Okayama after the concert?

Is it possible to leave my bags somewhere in Tokyo before going to Hiroshima/Okayama/???

Booked my airbnb in Shibuya, and have decided to drop Nikko. Is the trip from Okayama to Kyoto too rushed? I'm really only going to see a show and would plan to see it and Osaka on another trip to Japan in the future. Will I have a hard time making my 1800 flight on the 15th if I'm coming from Kyoto?

I was also wondering why include Ueno zoo. You can see those in your own city, and watching caged and locked up animals is not quite extreme enjoyment. But if you have any interest in seeing Tokyo at all, on Sunday Sept 6 go to Harajuku to see the girls in their wild fashions.
https://www.youtube.com/watch?v=3tY7jPFhTBM
Meiji Shrine and Yoyogi Park are there as well, and it makes a nice outing. You'd still have enough time for Akihabara.
https://www.youtube.com/watch?v=YY8iTdhnQ0I
I'd also suggest you keep Nikko - it is well worth seeing. So is Kamamura for that matter - in fact, adding Enoshima to it makes it a delightful day, and not some clone of Kyoto.
If you start early on the 11th, you can see more than the Peace Park. Shukkeien Garden is quite nice, as is the castle, plus going to Okonomiyaki Mura by the shopping arcade. But keep about ¾ of the day for Miyajima.
If you finish early, you could even go see Iwakuni, which is a stone's throw beyond - the iconic bridge and mountaintop castle are unforgettable.
https://www.youtube.com/watch?v=0COOZXi66mM
For the 12th, Korakuen makes a great visit - it's one of Japan's traditional Top 3 Gardens.
https://www.youtube.com/watch?v=5zAI3_N7NEM
But it looks like you could easily fit in more in the day - the castle is close by, plus the Handayama Garden is also something beautiful (and nearly unknown).
https://www.youtube.com/watch?v=JGQ8o7k9GbA
Going to Kyoto is also a great idea - Arashiyama has some sights, in fact few make to the northernmost place, Otagi Nenbutsuji to see the delightfully quirky and whimsical temple.
https://www.youtube.com/watch?v=efvtB_5jmjA
But if you've never been to Kyoto, IMHO the eastern side is much more interesting overall.

I took the 08:29 Shinkansen from KYOTO, changed to the NEX at SHINAGAWA (in Tokyo), had time to buy a Bento to eat on the NEX, and arrived at Narita around 13:00 for my 16:00 flight.

I assume you have 7 day JR pass, would be better to activate on the day 8, and use it for Nikko. You could still use for NEX on your last day to Narita Airport.

I would cut one day from Tokyo and go to Nikko or Kamakura a day earlier. Add that day to Kyoto. Like Mfedly, I don't want to get stoned but my money is on Kyoto... I would also throw in Kanazawa but due to the lack of time nvm.

Kyoto is really nearby Osaka. Sadly, Kyoto does not have much of a nightlife. Fortunately, Osaka livens up at night. Meaning Day Kyoto, Night Osaka.

For Okayama to Osaka, this is doable. My pal did Osaka-Hiroshima-Miyajima-Osaka in a single day. Don't let what you want stop you.

P.S. Recommended mode of transport for Hiroshima, Tram Car or rent a bicycle.

Recommended food for Hiroshima: Okonomiyaki
For Hakone: Anything Onsen related
For Osaka: Takoyaki
For Kyoto: yudofu, KaisekiRyori, shojinRyori, anything else
Miyajima: Oysters, fried maple leaves, deer meat (joke)

Thanks again for all the input. I think I'll take out Hakone and possibly Nikko, though I'm not so sure on that... Now I've got:

9/4: Tokyo - arrive late afternoon and check in and explore Shibuya (staying in Shibuya)
9/5: Tokyo - either half or full day in Yokohama, possible MONGOL800 concert at night in Shibuya
9/6: Tokyo - Finding out if there is a "cars and coffee" type meet this day, if yes, will attend that early then explore Shinjuku/surrounding areas afterwards
9/7: Kamakura and Enoshima day trip
9/8: Tokyo - possible Nikko day trip
9/9: Tokyo - last explorations of the city.. activities tbd
9/10: Hiroshima: early Hikari shinkansen to Hiroshima, hope to arrive early afternoon and explore the peace park and check in with my AirBnB before the 1800 Carps baseball game.
9/11: Hiroshima: Mazda museum tour 10-11:30, Miyajima rest of day, check out DUMB! records
9/12: Finish up any loose ends in Hiroshima early if needed then Shinkansen to Okayama: check in to hotel and check out Koraku-en. Sambomaster concert (doors 1700)
9/13: Kyoto: finish up early in Okayama and take the Shinkansen to Kyoto. Try to check out Arashiyama, ULTRA TOWER concert in the evening.
9/14: Depart: Shinkansen to NEX to NRT and fly out at 1830

It seems like events like concerts and sporting events start earlier in Japan than in the US, hopefully my schedule on days that include those will work out and I won't be in a time crunch trying to make a show/game. Does this schedule look like it works better? I need to fill out a couple of Tokyo days still I think. I will have a 7 day JR pass.