I never read the books and only saw the movies on my beloved vhs tapes. :) I was personally always drawn to cool things in the world of Hogwarts, such as the sentient paintings or the ghost in the bathroom. That's the kind of stuff that gave an air of this world living and breathing to some degree.
On the other hand, I've never liked Harry much, and I've always been disappointed by the magic system. I remember playing a Harry Potter PS2 game and only used one spell for 90% of it. Jinx Jinx Jinx Jinx Jinx Jinx Jinx Jinx Jinx.
I never even saw the movies past 3, but my cousin brought 6 over once and we tried to watch it. It was so damn dark I couldn't see what was going on. There's a difference between establishing an atmosphere and giving your audience eye-strain hernias.
Either way, to hell with this series. I literally couldn't care less about it anymore.