The series could really do with writing out a couple of the girls, but I know its not that kind of series. Just let more of them do the itachi thing and be there causing hijinks without actually being in the running.
Part of why is that at this point it feels like the 'actual' harem is Kuzuhana, Ushigome in a come from behind second, Inukai, and Kamogawa. The others are just kind of there at this point.