1) Anywhere on Honshu will have the distinct seasons that you stated. While I would not call Hokkaido's summer hot, it's warm enough to go to the beach. 2) Not in the major cities such as Tokyo or Osaka, but with the mass transit systems it is very easy to get away and out into the countryside.
If you want greenery and temples, then Kyoto, Kamakura, and Nara are just some of examples - there are others. 3) What is your definition of "pretty"?
I cant really gove you an answer,but what I can give you is a way to a solution, that is you have to find the anglde that you relate to or peaks your interest. A good paper is one that people get drawn into because it reaches them ln some way.As for me WW11 to me, I think of the holocaust and the effect it had on the survivors, their families and those who stood by and did nothing until it was too late.