What were they thinking when they created the original set plans and made Sickbay so big? It takes up a quarter of the sound stage! It seems to me that for the same money, they could have had a more varied bunch of ship interiors. Just cut Sickbay down to one room and redress it as the part that's needed. Were any of the four Sickbay rooms ever redressed as another set? We know that Engineering doubled as the gym ("Charlie X"), the theater ("Conscience of the King"), and Starbase 11's Computer Center ("The Menagerie"). The Briefing Room became the Rec Room in "Charlie X." The Transporter Room became the Chapel in "Balance of Terror." The Romulan control room was built on its own, midway between the Bridge and the Briefing Room.