Things I enjoyed:
* The scene at Michael's house when they test the lightsaber of Faith and conclude there are angels bound to the nails, just the opposite of the Fallen in the coins. This was a nice reveal. It is well set up, to make sense (I immediately thought of Uriel saying he is only allowed to respond in a mirror of the original offense). Now as I re-read the series I will look at the Swords differently and wonder what the angels bound to them are thinking.
* Harry summoning Molly. Their conversations were great. Veered from metaphysical (the Lady's mantle and how it meshes with Molly being human) to the power dynamic between them (negotiating a favor), to Harry pushing Molly to talk to her family. As a gay man who was terrified to come out to his parents, even though I knew they would love me, I understood Molly's fear.
* Mab getting sucker punched. You can be a big shot and still be caught off guard. I would argue the political effect of creating doubt about Mab's power was far more devastating than the physical act. Ethniu is going to pay for that in spades later. Based on the Christmas Ever story Mab is still around and Ethniu is not. Mab will enjoy seeing Ethniu get screwed, and at the hand of her knight.
* Seeing the Accord signatories come together under Marcone's leadership to defend Chicago. In the end, the fate of the mortal world rests with mortal choices. Marcone's choices to remind his guests of their obligations made a difference. I could otherwise imagine the group fracturing. While brief, hearing Ferro and Vadderung say that in short order they could lock Chicago down between the two of them is a tangible way to show how powerful they are.
* Binding Thomas. It was unique way to use Demonreach. I thought it was well-written and added richness to the island. I am wondering though how in the heck six thousand uber baddies got brought to the island to be imprisoned. I can't imagine them docile and chained up, riding a barge to the island.
I didn't enjoy:
* A lot of what others have said. It was short for a novel. It's unfortunately that the story was broken into two parts. It leaves Peace Talks with a lot of set up and no where to go...except wait.
* The bickering between Ebenezer and Harry. A little was fine. Eb turning into a raving mad man everytime they talked got old and seems out of character for someone as intelligent as Eb. Though maybe family is just his blind spot.
* Conjuritis. I don't know what the point was.
* The lack of actual peace talks.
* Murphy cutting off her casts and then voila, being able to catch a Valkyrie off guard with no problem at Chateau Raith. This is beyond credulity. Murphy herself says at the start that the doctors hope to get her back to a portion of normal functioning, not to athletic function. And she's walking and throwing down after weeks in casts? Either this is poorly written or there is something going on behind the scenes. Maybe a Faustian bargain was already made and she doesn't remember (intentionally). Maybe someone powerful hitchhiked into her body and is fueling her without her awareness.
And a theory or two:
* Now we know Starborn happens every 666 years. Anyone done any astronomy deep dives yet to see if there is a comet or some constellation that comes up that often? So who is hanging on, waiting? Rashid is the immediate first choice, given how old he is. Maybe Listens-to-Winds. I'm not sure how old he is. I don't think the Merlin or Ebenezer are old enough.
* I think Demonreach has a grudge against Rashid because he was the last Warden and he abandoned his post to become the Gatekeeper. I wonder if this will be Harry's path too. In the BAT the island is destroyed, the banefire is released, the baddies escape setting off the apocalypse. Since they are immortal they cannot be killed, but to win the battle they are exiled outside of reality. Rashid passes on the torch to Harry, and he becomes the new Gatekeeper. He writes the case files while manning the Outer Gates.