While writing my first 90 books I was magazine editor publisher book publisher executive etc. so I was established in publishing. three of my seven or so books were biographies of sports stars and really opened doors for me in that area.
Autobiographies are only useful as the lives you read about and analyze may suggest to you something that you may find useful in your own journey through life.
Great geniuses have the shortest biographies.
On the other hand when I give it closer thought I realize I'm not enough of a dictator to conduct an orchestra because it requires a pretty awful person. When you read these biographies of famous conductors they are all awful people who fail in their private relationships.
Great nations write their autobiographies in three manuscripts - the book of their deeds the book of their words and the book of their art.
When you write biographies whether it's about Ben Franklin or Einstein you discover something amazing: They are human.
I never appreciated 'positive heroes' in literature. They are almost always cliches copies of copies until the model is exhausted. I prefer perplexity doubt uncertainty not just because it provides a more 'productive' literary raw material but because that is the way we humans really are.