Soon I will be facing this issue from the side of a sensei...You will always have a sex dissatisfied because you can never fully have a utopia of the sexes, blending the sexes as one.... My solution is to separate the sexes in their own classes, only to bring them together occasional for the benefit of each other's practice. Will it work, I think so. Because the sexes naturally do separate on their own
You will always have a sex (sic) - gender that is - dissatisfied - HOW? In what sense can this be? Genders "naturally do separate"? Not in the world I live in...be it work, social life, family, close friends, acquaintances, grocery clerks, whatever, I have never had gender make a difference in who I associate with and I don't see it for most of the people superficial or intimate with whom I associate in most of these quotidian interactions.
I for one would never choose to train only with women any more than I would train only with tall people, one armed people, or Chicanos. Makes absolutely no sense to me. Humanity is humanity.
And in a martial arts context, the wider the variety of training partners, the better. Bring them on!