Would an "author box" type paragraph at the bottom of a hub be considered overly promotional?

This is rather common on online content. It helps the writer to establish a personal brand and you also get to know a bit more about the writer. As long as it is not too long and promotional, I think it is fine.It also shouldn't be obvious spam for many other personal online projects.

Yes, that method is fine as long as you don't abuse the linking and that your link matches the content your linking.

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.