I really like the concept of AP, but I'm not playing that fast that I'd need 2 per year.
In fact my current timeline and future plans are like:
2015-2016: Lost Mine of Phandelver
2017-2022: Princes of the Apocalypse
2023-2026: Curse of Strahd
So I guess I'm pretty much covered for now!
I still think the APs could be improved a little. Still require too much preparation. I really wish I could play them without preparation. Just read whatever is mentioned for the current room and have all the references that are relevant for that room at least linked to with page numbers.
Shorter adventures work just as fine for me as well, though. But I'm personally not the "just give me lore and I'll make my own adventure" type. I want to experience something I don't know as well, just like my players.