Thanks for the compliment! SPOILER ALERT ahead!

Someone actually wrote a ROS-based story in which gay men and women basically took over the world because straight men were too small and straight women too horny. "Rebalancing the Sexes: The World After." I'd include it in the series if I could find it. I responded to it in "Rebalancing the Sexes: Changing the World After."

Generally speaking, the Goddess of Love is mainly concerned about sexual and power dynamics between straight men and women. It is implied that a woman can shrink a gay man but most are cautious around women... even to the point of arming themselves, according to ROS:TWA. I haven't written a story about a gay man getting shrunk but I think the GOL would view it as nonconsensual, as opposed to a heterosexual male who is assumed to be fair game after the age of 18 if he's unattached. There would probably be punishments for the shrinker, much as there are punishments for women who shrink other women's boyfriends/husbands ("A World of Breasts and Buttocks.")

The addition of "bornsmall" men adds another complication. Boys born out of the back-womb come from different sperm than those born from the front. Given that there are genetic factors involved in sexual orientation, it seems likely that, once things sort out over the next generation, the Goddess has routed chromosomes so that straights are born out the back and gays out the front... thus uncomplicating things down the road. Eventually, gays start out life at woman-scale and stay there, while straights start out at man-scale and stay there. 

As far as transgender women, it's a factor we haven't dealt with. Perhaps the key is hormones, which would mean that someone who is receiving medical assistance to transition to male would shrink, while a man transitioning to woman would not. Still haven't given it much thought.

Thanks for your thoughtful question.