I always thought it would be fun to write a younger man/older woman romance (in which both are available - no cheating!) where the woman is old enough to be past childbearing age, because it would be an interesting exploration of the parts of femininity that are not linked to reproductive viability/peak collagen/etc.
I need all of my romances to have hard men and soft women or I'm out. I love the masculine/feminine polarity.
There's a graceful, classy, vulnerable, mature lady in the back of my mind somewhere, waiting to be written someday.
A long time ago, I spent a lot of time reading all kinds of stories on age gap message boards. There were some really hauntingly beautiful accounts of younger men who fell in love with women who were 50s-60s-70s, that all had a central theme of something about the woman spiritually embodying an essence of the feminine. Whether it was long hair, always wearing dresses, silk pajamas, something about the way they conducted themselves... These women never lost softness or vulnerability with age and I thought the appeal of a love story like that was really beautiful.