First Japan trip itinerary: sakura season

Hi all,
My husband and I are travelling to Japan this spring, arriving in the late afternoon of 30th of March to Tokyo, and leaving on the 12th of April. (Could extend the trip by one day too). I am the 'I want to see it all quick' type of traveller, while all my husband wants to do is chill! So I guess I'm trying to compromise here.
So far my planned itinerary looks like this:
30th March late PM - Arrival
31st March - Tokyo (staying in Shinjuku, must see the park with cherry blossoms early in the morning!)
1st April - Tokyo
2nd April - Tokyo
3rd April - travel to Kyoto (staying in Higashyama).
4th April - Kyoto (Kiyomizudera and Philosopher's walk early in the morning before crowds, other Kyoto attractions afterwards)
5th April - Kyoto (Arashyama in the early morning, Kyoto afterwards)
6th April - Kyoto (Fushimi Inari in the early morning, Kyoto afterwards)
7th April - Kyoto (Trip to Nara in the morning, quick visit to Osaka in the late afternoon/evening)
8th April - travel to Miyajima (staying at Iwaso). Would love to stop at Himeji castle - or should I do Himeji morning trip while in Kyoto?). Should we also see the Peace park in Hiroshima? (not too interested in seeing pain and suffering during our holidays, is it worth it?)
9th April - travel to Tokyo in the late afternoon (staying in Shinjuku near the station so that we can take a bus to Kawaguchiko next day, I like the idea of not having to change trains for this trip. Also the reason Kawaguchiko is last on the itinerary is because sakuras start blooming there later). Or is there a better way of getting to Kawaguchiko? Maybe should stay in Hakone instead for that night, and make equally long trip from there to Kawaguchiko? Or somewhere like Matsumoto? (a few hours in the morning of 10th would be enough for me to see it, I would be happy just seeing the shrine!)
10th April - Kawaguchiko (Staying in modern ryokan with onsen, the chilling part of our trip. Hope to see Mt Fuji and take some nice shots of cherry blossoms by the lake. Even if the weather isn't great, we'll just relax in the onsen)
11th April - Kawaguchiko (I must must must see Chureito Pagoda in cherry blossoms in the morning, fingers crossed Fuji won't be hiding behind the clouds. Saiko Iyashi village afterwards)
12th April - Travel to Haneda airport by bus (flying to Seoul, not booked flights for that yet)
As I said, we could extend by one day (our flight from Seoul is early morning of the 16th). Or does this itinerary look pretty good? Would you change anything? (sight-seeing in Kyoto is not actually set in stone, I just wanted to make sure I have 3 early mornings to see busiest sights before all tourists arrive)
Or maybe we should travel via Kanazawa to Kyoto, and spend a few hours or a night there?
All accommodation I've booked so far is cancellable, so I'm able to amend things.
Should I just book 2 week JR pass and not stress, start using in in Tokyo, or 1 week (as using bus for Kawaguchiko)?
Thank you all for your comments!

Around Lake Kawaguchi area is higher altitude than Tokyo and is colder in the north of Mt. Fuji.
So, it is difficult to see Sakura trees there at that time.

Yes on the 9th if you can to Hakone, why not? Saves going into Tokyo for one day, then backtracking to Kawaguchiko.

Perhaps you could save yourself one day in Kyoto. We took a train to Fushimi Inari in the morning, but continued directly to Nara, arriving around 14:00. After 2-3 hours in Nara around the main temples and feeding deers, we ended up by dinner time in Osaka to see all the neon lights. It didn't feel like too much, to be honest, but perhaps you could convince your hubby to have one intensive day, but then having a full day of rest in return!

"Kiyomizudera and Philosopher's walk early in the morning before crowds" - I dont think thats possible in one morning. Those places are not that close plus you will spend some time just being there (each place will take at least one hour). Also both places are popular so they will start to get crowdy shortly after 8:00am I think.

I would start with Philosopher's walk, or you can pick the one that is easier/faster to get to from your hotel.

Thank you all for your responses!

Definitely learning a lot from here. Would take note of these answers as well. Thanks!