In these early episodes we're certainly not hearing anything about Shatner lording it over the secondary cast regulars or cutting their lines. Hell, Takei credits Shatner with infecting people with his enthusiasm and professionalism.
Well, maybe not with the cast but in "The Galileo Seven" section the actor who played Commissioner Ferries describes how he had never been on a set like Star Trek. He said that Shatner basically told him were to stand and what to do and even Shatner was the one yelling "Cut" in the middle of scenes. He was shocked at the control Shatner had and says that the director just went along which surprised him because he had worked with the director before. It's also why I believe the director of "Shore Leave" (Sparr) was not asked back because he didn't put up with Shatner's B.S. even though Justman thought that Sparr did a great job under trying circumstances (and I agree)