https://b5books.com/babylon-5-scripts-overview/
They contain all of the original scripts for every episode (in some cases multiple versions) as well as commentary written by JMS about both what is going on on-screen and off-screen. They have some really detailed information on the challenges he faced running this show in an exceedingly raw and real fashion. Sadly, they are only available in print and are very expensive.
http://jmsnews.com has complete archives of all of JMS's usenet postings, which span the entire period the show was on the air (as well as many years before/after). Again, some of this is very raw, like where he discusses the feature film due to be announced "in a few days" about the telepath war (which we never got :().
Anyway, revealed myself to be a huge B5 nerd here, but, I do believe it was in a number of ways one of the most visionary TV shows on air at the time, highly serialized plots 5 years before the sopranos and computer VFX that movies couldn't touch at the time.