I think I'd rather see the same 3 second clips over 3 PVs like some other anime rather than see the expression sheets, random art and static screenshots (though I'm not going to complain about all the art...)
I get the suspicion there's going to be a few massive cases of quality, what with Yukiho's face melting off and one of Kotori's expressions having an eye melting off the side of her face.