If I was asked who were the bigwigs of the bible, who came to mind were Moses, Joshua, David, Isaiah, Ahab (ha!) and the likes. Never Ezra and Nehemiah came to mind. But now, after reading these two books in depth and the commentary, I just realized how big these two figures are.
On the other hand, I thought the difficult books of the bible were Jonah, Song of Songs, Romans, Revelations. Little that I know, that these two books almost got me out of my mind. Even with the commentary, I think I still got more questions than answers.