TNG had largely come into place with characterization started, courtesy of Gene who'd insisted on the characters having depth to them deeper than a parking lot puddle.

DS9 benefited from the idea of characters driving the plot rather than responding to it. Not something new or different, but novel to Trek where (as you noted) the idea was to keep things loose so writers had room to wiggle with writing characters. But the big thing in DS9 that made it stand out was the idea of story arcs and continuity that lasted longer than the end of an episode.

VOY and ENT basically suffered from the same executive mandate: Make the humans less interesting than the aliens. The expectation was that viewers tuned in to see all the new aliens that showed up, so write the humans as bland in order to make the aliens stand out more. This is how Garrett Wong got lumbered with a role so wooden, you could drill a hole and let out the sap. And why Robert Beltran basically prayed for death by the time the series was over. It only got worse so that by the end of ENT, the actors had little good to say about the series.

>I very much hope that Discovery is being developed from a standpoint
>of "why is everyone here, and what are we doing with them over the
>course of many, many episodes" and not simply "we need a guy on helm,
>because this is Star Trek and there's a guy on helm. Try and make him
>interesting, and we'll figure him out later."

I'm still rather ambivalent about Discovery, given the harsh gestation process its experience so far. The new look of the Klingons aside, the series has a lot to prove and I'm not sure it can rise to the challenge. I get that the first season of a Trek series tends to be one of its weakest, but we Trek fans have suffered through a lot of bad Trek in recent decades to just give it a pass on those grounds.

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CdrMike, Overwatch Reject