I never watched Babylon 5, but I did read the first volume of Earth One and liked it. It came across as pretty dark, and, given that Clark is supposed to be in his early twenties, it seems it's trying to hone in on some of the usual angsty young adult drama and questions.
What I found even more interesting was when I saw the trailer for Man of Steel, my mind immediately called up Earth One to compare it to....they both seemed to have that same "feel."