This is a super unpopular opinion but I absolutely HATED this book. One of the most disappointing books I've read, it even beat Half Blood Prince and I hated that one too. Before this came out, I was a massive Harry Potter fan. I participated in fandom, I talked about it, I used to play Harry Potter when I was little and even invented a game of Quidditch for us to play. I went to the book premieres and won the Harry Potter spelling bee at one of them. I was absolutely obsessed and so excited for the final book! Maybe my expectations were too high, I don't know, but this book was almost enough to make me fall out of love with the entire series and even now, a couple years later, I feel that I still love it out of nostalgia rather than anything else. I had some good times both online and off.
It was boring, much of the plot didn't make sense (or stunk of "Well, that was convenient!"), it could have used WAY more editing, the characters seemed way off, the relationships were terribly written, and what on earth was that epilogue? It was all about who got married and what mix of dead people's names their kids got. That's great and all but what about rebuilding the wizarding world and preventing something like that from happening again? Not only that but a lot of the conflict was increased massively by having the four Hogwarts houses and the associations with it, yet very little seems to have actually changed. I guess Harry telling his son that it's OK if he's in Slytherin is a big deal but it's pathetic that that's ALL we got. What about the prejudice about various magical creatures? What about their ignorance and scorn of muggles? But no, the resolution of the entire series is that the trio is now One Big Happy Weasley Family and Dead People: The Next Generation.