I definitely agree that Aragorn/Boromir in the films has excellent potential. "My brother, my Captain, my King," always gets me right in the loyalty kink feels. (I do like a Boromir Lives AU with Aragorn/Boromir, though they aren't frequently seen.)

Oh yes! I did a trilogy rewatch last Christmas (after missing out for a few years before that), and that line caught me right there in the feels again, even after two decades. And your fic sounds so interesting - would you mind sharing a link?