Yes..but it is really hard to explain correctly.
Even though Kiba gave his life to open paradise, and Darcia's eye infects it, it seems to me that it means there is no complete paradise here on Earth. There can be no good without evil, and vice versa, but this is my own belief and that's what it seems like to me. The part where they all come back normally and not knowing each other could be that they make have to take that journey all over again in order to achieve happiness again.
You asked a really deep question lol, I thought no one except me ever thought about that!
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.