I had great expectations for The House of Hades. Going into it, I expected it to be fully narrated by the Romans with Percy and Annabeth taking turns, so I was really surprised (and thrilled) to see that Leo and Piper also had the chance to narrate.
Firstly, thank Mr. Riordan for finally turning Frank into someone worth voting for. I've always felt like Frank and Hazel have been really underdeveloped, so I really enjoyed seeing them brought more fully into the series' story. I never thought I'd see the day, but I was actually freaking out at the epicness of Frank Zhang's battle skills at the end there. He definitely doesn't feel wimpy now, which is a relief. As for Hazel.... She had an interesting story and I enjoyed it. I think it's a smart move on Riordan's part to connect her skills to someone other than Pluto/Hades.
Without a shadow of a doubt, I do not hesitate to say that Leo had the most enjoyable storyline. His narrative was my favorite, well, next to Jason's of course. And he finally found a girl! *sigh* I suppose I mostly just like him better as a character than I do most of the others.
My biggest disappointment was definitely the lack of Jason and Piper. Narrative wise, Jason had two turns and Piper only had one, never mind the fact that Annabeth and Percy (two already-developed characters and a fully-developed couple) had like half the book. All I have to say is that they had better have more narrative in the last book than Percy and Annabeth.
Jason was hardly even mentioned until two hundred pages in. We were finally seeing what people like Hazel and Nico thought of Jason and I've been excited for that but he hardly had a part at all. As for Piper, she was treated as a minor character, pretty darn close to how Reyna was handled in this book. Not cool. I'm slightly frustrated with the lack of development and inclusion for Jason and Piper. But if the fifth book is going to have less Percy and Annabeth and more Jason and Piper, then I guess that's okay.
The biggest issue I had with this book was Percy and Annabeth's storyline. I'll be honest, I down right dreaded it sometimes. I know this sounds strange (it does to me) but I found Tartarus to actually be the dullest parts of the book. But instead of blaming this on my dislike for Annabeth, I actually have a real logical reason.
Percy and Annabeth are both already fully-developed characters. It seemed liked I was reading their part of the story only because it was part of the over all plot. Someone had to close the Doors of Death in Tartarus. But there wasn't really any character or story development with them. Everyone else in this book (even Coach Hedge) had more development than Percy and Annabeth, whose developemt I'd wager was pretty close to zero. I know people love them as a couple, and believe me, I want them to stay that way, but they've had a whole series. I just don't really see anything left to discover for either character.
I'm glad that we were able to see bits and pieces of what was going on with the Roman and Greek camps - definitely interesting. I actually, kind of wish the final battle could take place back where both camps could participate. And, oh man, Octavian just... I like Frank's suggestion. Catapult him, Reyna. DO IT! I really don't want to see either camp destroyed by each other or Giants.
There were moments when I felt like the characters were unnecessarily oblivious though. Hint, Nico's statement about the Athena Parthenos at the end there in connection with the fact that Giants can't be destroyed without the combined effort of a demigod and a god. I read said statement and was like, oh duh! So, yes, I did mentally say duh sometimes but not too often.
As for Piper's guesses about the Prophecy, I'm not really buying into the someone's going to die statements. I honestly don't think any of the main characters will die on us. These prophecies never work out the way we expect or are led to believe, so I'm not that concerned with someone we love dying (that includes Jason and Piper, people). But the other statements might have some real substance.
Overall: I really enjoyed The House of Hades but it wasn't has good as I expected it to be.