10 Star Trek: The Next Generation Episodes That Were Almost Completely Different
5. Chain Of Command
The main difference between the Chain of Command that was written and the Chain of Command that we got relates to the episode's length. First drafts given the green light as just a single installment, with no new Captain subplot, and Picard swiftly rescued at the end of the hour.
But in a theme that you should be quite familiar with by this point of the article, the central focus of the episode essentially being a "Two Person Play" between Patrick Stewart and David Warner proved to be incredibly cost-effective... and thus got extended over two episodes. You're right, there probably is a list in 10 Amazing Star Trek Episodes Only Written To Save Money.
However, the biggest thematic change to the episode occurs when Picard, Crusher, and Worf pay a short visit to Torman V in order to secure passage to their destination from a one DaiMon Solok. Originally, this scene was supposed to be a short visit to Deep Space Nine in order to secure passage to their destination from a one Quark.
However, despite it being filmed well after the pilot of Deep Space Nine, logistical rearrangements meant that it would air several weeks before Emmisary, and Paramount didn't like the idea of effectively introducing their shiny new show in a throwaway scene for The Next Generation. Time being short, DS9's Replimat set was simply reshot from angles that disguised it, and Arman Shimmerman was replaced by Lou Wagner.