Note that there are many possible interpretations of how time travel works, so the way you think time travel works might not be the same way as how time travel works on the show. By killing himself, Eddie caused a paradox - if Eddie dies, that means Eobard will never be born, and thus never go back in time, which led to Eddie killing himself. That's probably the reason why the wormhole opened up again and created the black hole - because nature abhors paradoxes, the black hole will destroy the universe to erase the timeline out of existence.
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.