If you were to actually think about this book a bit deeper after finishing it the whole plot would fall apart. 
It was a fun ride nonetheless. The rating is on pure enjoyment and not really on the quality of the plot and character development. The spooky scenes were good though.

Probably the best so far in the series. I still feel like it feels a bit too long but really good character dynamics as well as character development.

This was really bad. 

While I really liked all of the main and side characters, the writing was the biggest weakness for me. I think it needed a lot of polishing. And I do think it could have been cut down by at least 100 pages.