I had a hard time getting into this one. The "sacrifice" of Burnham was pretty well presented -- good job, SMG -- but the outcome was inevitable, and, of course, we had to wait until the very last second for the Red Angel to show up, like she was late for a bus instead of a time traveler who could appear at any point. Would have saved everyone some trouble if she popped in earlier and erased the neuro print before Tilly found it, wouldn't it?
The reveal at the end was one of Discovery's better twists, I thought, though the backstory seemed awfully easy and convenient -- "and then Burnham's mom built a time machine." OK, then. I'll have to see what they do with this, but I'm skeptical of the Federation having the capacity for time travel decades before TOS. Time travel in Trek isn't my cup of tea in general, and a suit that can let a person appear anywhere in time and space makes the spore drive look like nothing.
I wasn't sure what to make of the notion that the Klingons would use the time machine to destroy their enemies while they couldn't fight back. We're a long way from the honor 'n' glory Klingons of TNG, aren't we? It speaks to the mess Discovery has made of the Klingons that I have no idea if these Klingons would actually do such a thing. I guess the TOS Klingons would, so whatever. But it does seem like both the Klingons and Section 31 should be better drawn at this point.
Speaking of Section 31, I actually kind of like what the show's doing with Leland, and that's making me like MU Georgiou even less. They keep presenting him as a "shades of gray" character, which I could find interesting, but then they have MU Georgiou camping it up and making the whole thing feel like a cartoon. I do agree with the notion that it feels like she's wandered in from another show. I like that they seem to be trying to humanize her, but that seems like a long walk for a short drink of water.
Final random thought: After seeing that Ariam's replacement is played by the old Ariam, I wondered if there was truth to the story about the actress being allergic to the makeup or if that was just cover because they wanted to keep her on the show.