Thoughts on "Another Note" book?

I just read it and I thought it was just terrible. I love L Change the WorLd (book) and was really looking forward to reading this book. I was irritated my so many details that were either completely wrong or just didn't feel right eg: Mello writing it after he died? Mello's writing is nothing like he was in the manga and he felt like a totally different character, same for Naomi she felt like a different character as well, shinigami eyes now apparently tell B how people would die which they didn't do in the manga, no explanation of how B got the eyes.

I was really disappointed because when I started the book and realized that Mello was the author and referenced his own death I was really interested in seeing where that went and thought that was going to be part of the story. Same for the shinegami eyes but no, neither of these things are ever explained. The actual Death Note elements felt so tacked on and pointless that I didn't get anything out of this book. Apart from a certain twist, it was smart and I wasn't expecting it. Although I don't know how L wouldn't have picked up on it.