I was thinking the other day what I would want from a version 2, and I got an idea. "Smart buffering". I want storage on the AirPods themselves, but I don't want to manage that data. Also, considering the size, I don't want a whole lot. What I imagine is that I'm listening to audio, on any device through any player, and the AirPods would buffer whatever I'm listening to, or perhaps what I'm going to listen to. If it is a podcast, it somehow caches a the entire podcast to the AirPod (or best it can) so I don't get dropouts when I've gone too far from my Bluetooth device. Same for music, except maybe it can cache the current and next song.
I know some would want like 8GB of storage so they can just exercise or whatever with the AirPods without a watch or an iPhone, but I think maybe mine would be realistic enough for everyday use.