That's a pretty big body count. Let's go through the cast and see who may have their Plot Armor revoked.
1. Unlike lots of fans, I think Murphy is safe until Body Slam. She's probably not going to be in Mirror, Mirror much, and I don't see Harry having is act together on Christmas Eve if she's been dead for just a few months.
2. Thomas might die because he's gonna be a dad. He may be in a Changes-type situation where he's got to go to the mat for his kid, but comes up short in terms of making it out alive, though he'll succeed in setting things up for said kid to have a shot at survival.
3. Will and Georgia probably won't be in it much. Plus the Alphas have been through enough since Turn Coat. I think they're reasonably safe.
4. Maggie's not going anywhere.
5. Butters just got his new job. He'll be fine.
6. Marcone is going to be important in some way to the BAT, I think, so I'm pretty sure he'll stick around for the rest of the Case books.
7. Hendricks might die. It would be one of the fastest ways to get Marcone to unload on someone.
8. Gard's also a possibility. Killing a Valkyrie is a reasonable way to set up someone as a legitimate threat. And if Hendricks is still alive, he'd go ballistic (literally; the dude has used a helicopter's chain gun before). Also possible that the two go down together.
9. Bob's Bob. It would take some serious plot events to get him dead. Maybe the White Council finds out about him? That could be fun.
10. Justine's unlikely; pregnant women are rarely killed off. I think she's safe for now.
11. Lara Raith... I don't know. I can go either way on her getting offed. It would have to be a coup attempt, I think, possibly by Thomas in a bid to secure a future for his kid.
12. Michael + Carpenter family. I think they'll be fine, cuz they're in Christmas Eve.
13. Molly'll outlive us all.
14. Mab's still necessary. And in Christmas Eve, along with Kringle. So maybe "Vaderrung" dies, while Kringle lives on, or something.
15. White King might go down if his weakness is revealed. Again, possibly by Thomas, during a complicated coup.
16. The Merlin, I'm sure, will live.
17. Martha Liberty and Listens-to-Wind may get offed, but the fight would be spectacular.
18. I don't think Eb will die just yet. His death will have significant ramifications, I think, and I can't see the next book failing to explore those. Kinda feel the same way about Martha and Injun Joe, but I could be totally wrong.
19. I can see Luccio and/or Carlos dying. That has emotional impact for Harry and plot significance without really needing a ton of follow up; it'd mostly be about how Harry feels about it, I think, rather than upsetting the balance of power even further.
20. I doubt we'll see Goodman Grey, the Denarians, Binder, or Valmont, so... Hurray, they get to live!
21. Ivy's death would have catastrophic consequences, I think. So I'm pretty sure she'll make it.
22. Kincaid, on the other hand, is due for some real backstory. We might get a full exposition dump and a Day in the Limelight chapter for him only to watch him die in a really cool way. Plus, Murphy's never confronted him about shooting Dresden, and I kinda want to see that.
23. Christos might snuff it, if only because this book is bound to have political gamesmanship and I'd love to see him get caught up in his own scheme.
24. I feel like Vincent Graver, Chicago P.I. will return soon, and he'll possibly get killed so Harry can feel guilty about getting him involved.
25. Toot Toot is indestructible. You cannot destruct him. Go ahead and try it.
26. This might be the book that brings back Tilly. He probably won't die, though, since I see him playing a big role in the mortal government response to supernatural threats eventually.
27. Cowl and/or Kumori are, in my opinion, likely to rear their hooded heads again. I don't think Cowl's going to die just yet since he's a Bigger Bad type character, but we might find out who they are, and Kumori may die unless her real identity is one that's too important to the plot (like if she actually is Elaine).
28. On that note, Elaine may show up. If so, I expect her to live.
29. Titania's death would screw up the world for a while. So I think she'll still be kicking. Ditto Sarissa and the Mothers.
30. Mouse, dying? Not a chance.
31. Maybe we'll finally find out if Abby's dead.
32. Mac will do a brisk business during the Summit. Since everyone is supposed to be playing nice, I expect his neutral territory to be respected. I don't think he'll die.
33. Mister's as indestructible as Toot Toot.
34. Lea's death would be almost as earth shattering (especially to Harry) as Mab's. So I'm pretty sure she'll live.
35. Murphy's mom is 100% dying, in my opinion (pretty sure this is what Jim meant by his "Murphy's funeral." tweet), and it'll be entirely unrelated to the main plot. It'll just be one more thing for Harry to juggle.
I think that's it. That's what I think, anyway. Not too many deaths, but I might be surprised. Jim's done it before.