Itinerary including Dec14 Osaka/19 Yokohama

Hi guys! I will go with my partner to the Club Soccer World Cup in Osaka and Yokohama this December and we would like to go to other cities before, between and after the games, may be Hiroshima, Kioto, Tokio, Nara, Kamakura, Kobe, Nagoya and Hakone. We are planing to stay 14 days, arriving on December 8 and leaving on December 21.

So, What itinerary could you recommend us taking into account we must be in Osaka on December 14 and 19 in Yokohama?

We know is a bit tricky question but we want to make our first trip to Japan in the most efficient way.

Thanks a lot!

December
8 Land in Kansai Airport, take limited express train to Shin-Osaka, take shinkansen to Hiroshima. Stay the night.

9 Go to Iwakuni, go to Miyajima

10 Explore Hiroshima, shinkansen to Kyoto. Stay the night.

11-13 Kyoto.
Northern, western, and eastern regions. One region per day.

14 Make a day trip to Osaka for the game. Explore Domtombori for dinner/supper and pop by Osaka castle just to take a look.

15 Day trip to Kobe or Nara.

16 Go to Tokyo.

17 Day trip to Kamakura
18 Day trip to Hakone
19 Day trip to Yokohama
20 Tokyo
21 Tokyo

get on Yokosuka line from Yokohama station to Kamakura station,arrive in 30 minutes.

get on Tokaido line from Yokohama station to Odawara station and arrive by 1 hour.

It's a mountain railway to Hakoneyumoto(Hakone Town in a hot spring) station at the base in Hakoneyama(Mt.Hakone) from Odawara station, 15 minutes.
It's more mountain railways to the base in Hakoneyama(Mt.Hakone) and Gora station, 40 minutes.

Kamakura　Hakone　Yokohama
Than order
Hakone　Kamakura　Yokohama