In the interest of reining this back in...
A lot of ideas are shared on this forum regarding new projects for Star Trek whether it be film or television.
What I find odd among the divergent ideas are those ones pitched that seem to have little to do with Star Trek other than slapping on the name. To me such ideas would serve better as wholly original non Trek projects.
For me Star Trek is "Space, the final frontier. These are the voyages..."
I know that disappoints some, but thats what it is and thats what the broader audience recognizes. It's not predominantly politics and war (seen in DS9) and gritty and nihilistic like nuBSG and Sopranos.
Why did TOS click and go on to enjoy an expanding popularity? Why does it still draw younger viewers? Why did TNG click? Conversely why did DS9, VOY and ENT not really click and drew diminishing numbers of viewers?
So what does Star Trek have to have to remain recognizable? And what things are distinctly not Star Trek?
Thoughts anyone?
I read some one post that TOS and TNG were the right shows at the right time. TOS did have a good, balanced mix of adventure, humor, and intelligence. It had an abundance of social issue source material and successfully posed important questions in a fantastical environment where viewers felt safe pondering them.
I haven't seen anyone post about NASA and the Apollo program. TOS also had to compete with live broadcasts from the moon, and other real life, exciting space news of that time. So I would assume that the cancellation of Apollo may have contributed significantly to Trek's resurgence in the 70's.
I also think for Gene, TNG was really just TOS-2.0; it was his chance to do ST the way he always imagined it could be.
I know what critics and fans say: That DS9, VOY, and ENT failed. But you know what? They didn't fail me.
Admittedly, I didn't appreciate DS9 when it first aired, but thank God for Netflix for giving me a second chance to see what diehard DS9 fans saw in it. VOY was my favorite from the start - I loved all the characters and almost every episode, and I'm proud of that. And once it found some balance, I really liked ENT (including Bakula) and loved the direction it was headed in. And season 4 gave us the best TOS back story we could have ever dreamt of.
Look, we're all on here because we're core Trek fans. For all it's flaws, stumbles, mishaps, and corniness, we love what Trek has become over the years, decades, and now, generations.
I don't want Trek to change. I want it to evolve, just like it has been for 50 years (woot!)
So to answer the OP's original question, "What does Star Trek have to have to remain recognizable?" It just has to have more Trek.
Yes, I have my own opinions about it: I do think Trek should embrace the new world of shorter seasons, complex plots, ensemble casts, and arching story lines. But I also don't think it's necessarily a bad thing to keep one foot in the episodic format if it works. And I'm definitely not saying we should be petitioning for
Game of Thrones in Space or
Star Trek Wars. I'm saying that Trek should just use the new entertainment environment to show us more of the universe we love and what Trek can be. As long as it's done with integrity, wit, and respect for established history, I'll be excited to watch it.