I think on previous readings/viewings, the Prisoner of Azkaban was my favorite book/movie. Wacky things happen, you get some cool magical thingie moments (the Marauders map is cool as is the Monster Book of Monsters ), you see a bit more of the magical world (Hogsmeade!), and you learn a bit more about Harry’s parents and how Hogwarts was before Voldemort was at the height of his power.
Speaking of which: another strength of this book is that it basically completely ignores Voldemort. It’s a nice switch; one that we don’t get to see again.
Also, I like Lupin. He’s a pretty cool person to be around, if perhaps not the best teacher ever. Also his class focused just a bit overmuch on the creature side of the Dark Arts (shouldn’t most of those be Hagrid’s domain?), but perhaps that’s a third year thing.
Sirius, on the other hand, I don’t really as much for. Any ‘only person ever’ has to earn it and I really don’t think he did. That and he’s just so driven. After 13 years in the worst of prisons, I get it, but it doesn’t make me like him or want to read about him terribly much. Also, how in the world did he get the Firebolt ?
Random things that don’t really make sense:
No one tells anyone anything. So many problems in so many books could have been averted if people just talked more.
Time travel . One one hand, it doesn’t make sense to give it to teenagers (no matter how gifted). On the other, there is so much more they could have done with it. And knowing what comes next… why does it never come up again? (Cursed Child doesn’t count).