For those of you who read genderbent fics, what do you look for? How much do you want the characters to change and how much do you want them to stay the same? How much do you want gender to affect the actual plot.

A contest winner who won a fic from me requested a female version of the particular slash ship the contest was about. I've never written a genderbent fic and they said they didn't really care what they wanted.

I'm having trouble figuring out exactly how much gender should impact the plot and characters. On the one hand, the fandom is Tolkien, so there tend to be some more gender roles and ways female characters are vs. male characters. On the other hand, the two characters are basically evil angel/gods who wouldn't really care about convention or what people thought of them.