Meant to reply to this earlier. Oops.
Burnham was always *the* protagonist, but I was hoping the rest of the cast might be important in ways other than plot elements. Anyone not related to Burnham's character arc is a cypher and lucky to even have a name…
It certainly looked this way for a while, but I think the show's moved past being Burnham's story exclusively. Tilly and Saru clearly have their own story arcs, and even the semi-nameless bridge crew have gotten some lines. Why their names have even been spoken aloud! (and not determinable solely from the credits - which was a problem).
I've also said repeatedly, Tilly's role in the story is to be bonded to and die at Tyler/Loq's hands in order to drive Burnham to move past her affection and kill him. (Likely with last words related to "at least I got to be Captain… for a little while…") I'm now expanding that prediction to alternatively include Lorca. And Stamet is also likely fated to die so the secrets of the Spore Drive are lost.
I'm pretty confident Tilly, Saru, and Stamets will be around for season 2. I'm not sure they would have survived Fuller original design for Discovery - i.e. the anthology series -- but I doubt they're going anywhere now. Well, maybe one of them will go out in a blaze of cheap, overwritten drama. Admittedly, that's been a persistent issue.
(Of course, he also wanted the show to be an anthology series, with each season set in a different era. That would have been lovely, albeit likely expensive. We're left to only imagine the adventures of the Discovery-A in 2275, Discovery-B in 2300, and the Discovery-C in 2325…)
I would have loved to see his version of the show. But I can see how that structure would have raised the show's cost from "a big gamble" to "inarguably prohibitive". Each season being a commentary and expansion of a different era of Trek, complete with its one theme/set of themes could have been fantastic.
Another persistent problem with the Discovery we actually got is it has no answer to the question: why is it a prequel to TOS? Absent the original plan for the series, there really isn't one.
I am curious (morbidly curious?) and uncertain where things are going.
That's what keeps me interested. Despite the missteps and bad plotting/writing, I am legitimately surprised by something pretty much every episode. I didn't expect from a Trek show. Case in point, I was somewhat disappointed by the final episode in the Mirror Universe, but I didn't see Burnham saving/kidnapping Empress Georgiou coming - prolly should have, but didn't.
As for this week's ep., I found it much better. Saru makes a good captain. Tilly's response to Ash in the mess hall was so, so Starfleet, and Burnham's scene with Ash looked like it was going to be a trainwreck, until it became something else. Nuanced, graceful, topical even. Believable, despite the gonzo sci-fi setup.
And I didn't see Mirror Georgiou being trotted out in a Starfleet uniform, complete with absurd cover story, either. While I admit that also probably counts as cheap, plot-y drama, it totally worked for me - I think because the episode really sold the Federation's desperation. The actress playing the admiral did a great job. Almost coming unglued, but not quite (if this were TOS she would have wolfed down a generous helping of scenery).