If Butcher had tried to run "Harry's death is a world-spanning catastrophe" early in the series, it would have come off as rank Sue-ism, but at this point he's got the chops to rig it properly. ("Harry's mistakes have killed him and also caused a world-spanning catastrophe;" easier to swallow.)
With Harry mostly intangible for the duration, we get our ensemble cast back to carry the real-world part of the plot. Expect plenty of Murphy, Molly, Butters, Mort the necromancer, and many others. Some are absent, for interesting reasons.
I sense there is a discussion to be had about Molly -- no longer an apprentice -- but I don't know if I can start it. I can note that she has become an adult, a wizard in her own right, and terrifying; Harry absorbs all these facts with surprise but no shock. (Power is always terrifying in this series. Molly has been playing the humble student for several books, but if you thought she wasn't dangerous, you've forgotten her introduction.) At the same time, Harry still does not hesitate to judge her as a student. You can take that as the author's blindness or the protagonist's. I think the author leaves the argument pointedly unresolved -- and there are more books coming -- but we'll see.
(I can also note that Molly stars in a brilliant psychic battle scene late in this book. I don't know who plays Molly in the (nonexistent) seventh season of the (actually cancelled) TV series, but she's going to have so much fun filming this story...)