This is why Shatner told Takei "but all the action takes place on the Enterprise." At the same time, being Captain of the Excelsior in Trek 6 gave Takei his best material in the films. Actually, having a second regular ship in the films earlier on might have opened things up a bit. Or maybe there would have been no USS Grissom and Sulu would have been obliterated in TSFS. Or, more likely, on the planet with David and Saavik. Then Sulu would have had a larger revenge arc then Kirk. "Kruge killed your son? Boo hoo, he wiped out my entire crew!"