I've now read all 6 books in this series. In a nutshell, these are books I love to hate. The storyline is engaging, and I definitely wanted to keep reading to see what happens to all the characters. Having said that, there are SO MANY historical inaccuracies that it was almost, but not quite, enough to make me walk away. Other readers have pointed out some of the obvious errors, like showers in the NYC tenements, etc. I'll point out a couple of things that just about drove me crazy: (1) the author's constant use of bad grammar in an effort to make the dialogue more authentic -- at least I can only assume that's why she uses it. Case in point, "Me and Caleb used to go there when we were younger." (OK, this isn't a direct quote, but you get the idea.) Every time I read another example of "Me and ____ did such and such" it makes me grit my teeth. (2) Getting a very simple detail like the Ides of March incorrect. In Book 3, one of the chapters is titled, "March 10, 1931," and starts off: " 'The Ides of March,' Jonathan grumbled as he carried Jean back to his bed." NO! NO! NO! The Ides of March is the 15th!!! The Ides of any month is the 15th!!! IMO, this sort of error is inexcusable. (3) In Book 2, a large chunk of the plot is "lifted" straight from the movie "Ghost." Hardly original.
It should be noted I lowered my rating for Book 5 by 1 star. Yes, I understand it's a "novella;" yes, I read it; and yes, it does relate, at least somewhat, to the rest of the series. BUT, I simply cannot rate it any higher. The storyline would be perfectly fine without this, and, IMO, it really doesn't add much.
Overall, the storyline was entertaining. Some of the characters were great; some not so much. I found Ava to be an insufferable, whiny witch. The predictability of many plot points was a little irritating, i.e. who was related to whom, who was doing what, etc. And while many probably see Book 6 as wrapping up all the loose ends, I don't. When I read books that crawl through the minutia of daily life, only to then cover decades (in this case, 41 years) in a few pages, I am just plain annoyed! It's as if the author decided she was tired of writing, tired of the story, and tired of the characters -- so jumped over a lot of years and slapped on a silly ending.