Article at Reactor about the planning it took to get five years of Babylon 5 to tell a complete story, the curves thrown at it by outside circumstances (actors leaving, premature cancellation, etc.), and the seat-of-the-pants swerves that sometimes worked out better, sometimes not as good as what could have been.
Babylon 5 Was the Ultimate Exercise in Plotting vs. Pantsing
In its very bones, Babylon 5 was a unique experience. It was a bold attempt to experiment with the conventional format of TV, with a serialized storyline and continuity, unlike earlier shows like Star Trek or Quantum Leap or any number of other “story of the week” style science fiction programs. Here in our current era, post-prestige TV, that kind of storytelling is common, but in the 1990s, when Babylon 5 first entered pre-production, it was nearly unheard of.