Okay, having finished the entire episode, I like it a bit better. I still think it was very flawed, and I'm rating it worse than the rest of the MU episodes (6/10) as a result.
The good about the episode was basically the visual elements. The ship shots seemed better than in past episodes, and the fight choreography was excellent - action movie level. I liked the twist of Georgiou surviving, which was unexpected. I liked the ending scenes of Stamets navigating the network as well.
Unfortunately, the dialogue and plotting was action movie level dumb as well. This is Trek for people with double-digit IQs. Lorca's character had zero complexity - he was just a dumb MU heavy who was destroyed for nothing. All of the characters had dialogue which was just too on the nose, with tons of exposition and/or technobabble as the plot needed. As I mentioned, the added stakes of the entire multiverse being destroyed made no sense - if all someone needed to do is construct a big ship powered by the mycelial network, it would have been destroyed billions of years in the past, given we're talking about an infinite number of universes. And the ending scene where the "battle lines" updated without any word from the federation was just eye-rollingly dumb.
The worst by far however is given it appears that the Klingon War might have been lost by the Federation (unclear based upon the trailer, as others have noted) we might be heading for a reset/time travel episode. This potentially means that the entire season was for nothing, and they might just do a mulligan.