I did think of this possibility, though I have my doubts whether the editor would go for a trans protagonist. That wouldn't stop me from writing a story if I thought I had a good idea, of course.

Another possibility is an intersex protagonist.

Complexity that is central to (or at least pertinent to) the story would certainly lead to plot and character development; my best stories/songs take more than one idea thread and weave them together; so far, however, nothing has sparked around the thought of using a trans protagonist.

I would want to do something more than just a trans-self-discovery story or a trans-coming-out story...