Wasn't this show's director the one who also did Persona Trinity? That may explain the somewhat unengaging feel.
I actually don't mind this series though. The characters still aren't "likeable" as far as likeability of anime characters are concerned, but I don't dislike the overall flow at the moment.
I was a bit surprised to hear that Aoi is European. You get so used to seeing characters in a variety of hair colours that only the very obvious becomes immediately apparent.