I'm still utterly baffled by this whole "Mary Sue" criticism. I really am. What has she done that merits this? Is she a better fighter than anyone? Well, no, she routinely gets her ass handed to her. Is she a better pilot? Well, no, Lorca and Pike as well as others are better pilots. Smarter? Nope. Solves every problem when no one else can? Nope. Better engineer maybe? Nope, there are several engineers ahead of her on that one.
So, what is it? Is it because she has more screen time? Or that in the first season most of the plots placed her at the center? That's not a Mary Sue, that's just a protagonist. Is it because she's the focus of much of the show, whereas previous Star Treks focused so much attention on the captains?
Let's not forget here, by yesteryear's standards, we're not even through a single season yet. Yup, the show focuses on Burnham. That's true. She's the lead character, whereas previous Treks put the Captain in the lead. Again, still not a Mary Sue.
It would really strengthen people's criticisms if they could avoid using such loaded shorthand that really doesn't apply here.