Honestly, a dozen of these would have been a better choice I think than two or three of the Planet Killers.



JMS' original plan for the Vorlons was to have one large "city ship" that served as the Vorlon home planet and it would be destroyed by the Shadows at some point in the show's run. But plans change, and things happen, and so the story of the show changed over time (even while in production!). The show's production crew still wanted to have a big Vorlon ship though so they came up with the Planet Killer.



I think all of the Vorlon ships in the TV-Movie Third Space were a different design than what was in the show.