More romance stories should give the woman the protagonist is dating a little sister, so he can be the stepfather who steps up for her and the adopted big brother she always wanted, enabling cute scenes, and impress his woman with what a good brother/father/older relative he can be, all without dealing with any of the baggage that comes from the woman being a single mother. It also lets the little sister create problems the woman can't create for herself and others without looking incredibly stupid and childish. Sure, it means more work for the author. It means you have to write a little sister, not just a baby-shaped helpless object that artificially creates drama or reasons for the protagonist and his woman to stay together. But after seeing how good it was in one manga, I wondered why it's not more common.
Also, why aren't there more stories where the male protagonist has to crossdress to sneak into an all-girls school for exclusively benevolent reasons, like wanting to be a hero and fight demons in a world where only women are allowed to learn magic because of arbitrary and nonsensical societal beliefs reinforced by an insane dogmatic society? Feels like most stories just use the idea for an excuse to contrive drama sometimes instead of deeply thinking through the premise and its consequences and how it feels for the protagonist and others close to him and others who hate him.
Let me know if there are any other underrated and underexplored ideas and tropes you can think of.
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