Ira Steven Behr called out what he believes was a "tragic mistake" of Star Trek: Deep Space Nine

Star Trek took a vastly different path when Star Trek: Deep Space Nine was created. Gone were the days spent in space iwth a captain leading the ship. Instead, a space station that was previously occupied by hostile aliens was the setting. The interior was dark and gloomy and offered the perfect opportunity for the series to cover some equally dark storylines. But first, the producers had to find the commander.

He was envisioned to be a commander in his thirties who was wrestling with feelings of doubt and defeat. Instead, Avery Brooks was cast as the commander of Deep Space Nine, and Ira Steven Behr, as The Fifty Year Mission The Next 25 Years from The Next Generation to J.J. Abrams by Mark A. Altman and Edward Gross reported, thought that was a tragic mistake. Not the actual casting of Avery Brooks but the fact that he was a man in his forties who was still a commander.

"To the fans, the hero of Star Trek is the captain, and if you're not a captain, there's got to be something wrong with you—you're the star of the show and your'e not a captain and you're a man already in your forties?"

- Ira Steven Behr

In all fairness, Brooks' character had gone through a tragedy with the loss of his wife. He was a single parent raising a son, and that was obviously his first priority, not his career. On Star Trek: The Next Generation, Commander William Riker (Jonathan Frakes) turned down opportunities to captain his own ship, and the fans didn't question why. To do so would have meant he would have had to leave the Enterprise.

With Sisko, while it was a small surprise that he was still a commander, Deep Space Nine wasn't a ship that needed a captain. And Sisko's rank was never a problem as he wasn't outranked in the chain of command. There was never any doubt that Commander Sisko was in charge of the space station, and when he did get a promotion to captain, it was done so without much fanfare.

Would Star Trek: Deep Space Nine have been better had Avery Brooks been cast as Captain Sisko from the start? I can't imagine that to be the case. In the Michael Bay produced series, The Last Ship, the "captain" of the ship was actually a commander, but there was never any question as to who was leading the shp. So having a commander at the helm of a naval warship was essentially the same as having a captain. And it was the same for Deep Space Nine. For all intents and purposes, Commander Sisko was the captain; he just didn't have the rank yet.