Help with itinerary timing late february

Hi everyone, looking for help planning part of my itinerary. For the first part of the trip which I need help with, my girlfriend and I will be travelling alone and then the rest of our group arrives 2/28. We were there last year and already saw a lot of the major attractions in Osaka/Kyoto/Nara/Tokyo. I appreciate the feedback and any suggestions!

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Day 1 (2/21): Arrive Tokyo

Day 2 (2/22): Setagaya Plum Blossom Festival or Mito Festival (Is either of these worth it?)

Day 3 (2/23): Day trip Yokohama/Kamakura/Enoshima

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Day 4 is where I'm not too sure if I should spend more or less time in certain places and what I can do in the Winter here.

Day 4 (2/24): Romance car and explore Hakone by day and do the loop, then head to Kawazu and spend the night there. (Not sure if that is too much for one day?)

Day 5 (2/25): Kawazu > Shizuoka? Or should we go to Shimoda?

Day 6 (2/26): Shizuoka > Return to Tokyo

Day 7 (2/27): ?Tokyo? or possibly extend a stay at one of the above places

Day 8 (2/28): Need to be in Tokyo this day as friends arrive

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We will be there in the winter, open to other suggestions if you think another region would be cooler during this time. But if this is a good place to go, I would appreciate advice on the timing and if we should stay longer in some of these places.

Once my friends arrive we will be heading to Nagano and exploring that area. Thanks everyone!