I'm impressed with the way the latest two episodes have been handling Aoki. They have acknowledged and even lampshaded his utter irrelevance in the show (he reminds me of Akarin, his lack of presence is his only distinctive trait
) so far and had them do something about it. He has received nowhere near as much focus as the other characters are, but at least he is actually relevant now, if only a little bit. He was barely even visible before.
My only gripe is that I wish he had found a more original way to help Yui. Taichi has already used his libido (and literally his balls once) multiple times to solve problems... it's getting a bit old.