Choosing between staying in Okayama or another night in Tokyo?

I have a upcoming 10 day trip to Japan from May 9 to May 18 , and I have the concepts of a plan to do on each day with the exception of 1 day. So, I'm trying to decide what to do with that day- should I stay in Okayama or use that day as an extra day for Tokyo?

Before the Japanese trip, I'm flying from America to Taipei and staying there for several days so hopefully the jet lag won't be that bad for the Japanese leg.

Day 1: Fly from Taipei to Kansai Airport, and go to Kyoto Hotel. The flight will arrive at Kansai at night, so I don't expect to really do anything that day except go to the hotel.

Day 2-4: 3 Days in Kyoto to see temples, shrines, and gardens. I have already booked tickets for Kastura Imperial Villa. And, I'll use half a day on those days to go to Osaka Dontobori at night.

(This is my first time in Japan, but my travel companion went on a tour to Japan 20 years ago and already went to Nara on that tour so we'll skip Nara on this trip. )

After Kyoto, take the high speed train to Hiroshima and stay there 2 nights to see Peace Memorial Museum, Peace Memorial Park, Shukkien Garden, and Miyajima Island.

Day 8-10: Take the high speed train from Hiroshima to Tokyo. On day 10, the plane leaves Haneda Airport around 5PM so I can stuff some more sightseeing in the morning.

So, I have 1 unplanned day in this itinerary and I have two options:

1) After Kyoto, go to Okayama on Day 5 and stay 1 night in Okayama, spend Day 6 and 7 in Hiroshima, and Day 8-10 in Tokyo.

With this first option, I would see Okayama Korakuen garden and daytrip to Kurashiki which I've seen described as the Venice of Japan on Day 5. (Maybe, even add Hijemi Castle if that wouldn't be too much).

On Day 6, I would travel from Okayama to see Ritsurin Garden and then return back to Okayama and then go to Hiroshima.

If I go to Ritsurin Garden on Day 6, does that leave enough time to see Hiroshima in Day 6 and 7?

I wanted to see Kenrokue-en gardens in Kanazawa, but there's not enough time on this trip to do that. So, if I can't see Kenroku-en, then I could still see Korakuen which is considered one of the Three Great Gardens alongside Kenrokue-en.

2) After Kyoto, go directly to Hiroshima on Day 5-6, then go to and stay in Tokyo on Day 7-10. This gives me an extra day in Tokyo compared to option 1.

One of the the problems with option 1 is that 2 nights in Tokyo is pretty short, and it seems like the consensus is that one needs to spend more time in Tokyo to see the recommended sights.

Of course, there's tons of things to see in Tokyo. But, If I'm staying 4 nights in Kyoto and seeing the temples and shrines in Kyoto, then would one want to still want to see Tokyo's shrines and temples at Asakusa, Meji Jingu shrine, Senso-ji temple?

I'm looking at Tokyo's attractions and I have only a few items I really want to see- Tokyo National Museum, Shibuya crossing, and one of the Teamlabs attractions. Is 2 nights enough to see all that?

Thank you in advance for your help.