I undertook a fun little mental exercise the other day. The ongoing discussions concerning gender equality in the SciFi/Fantasy community (for instance, this excellent thread on Mythic Scribes) got me thinking about some of my own characters. Personally I do tend to default characters to male - that is to say, unless there is a reason for a character to be female they are written as males. This has resulted in what even I can admit is a noticeable deficit of female characters thus far. Whether this is because I myself am male or because of cultural programming, I leave to others. It is a situation that I intend to change, though.
Anyways, back to that exercise: I went through a few of the stories I have in my head and flipped the gender of some of the main characters, trying to imagine the difference it would make in the story.
By and large, in many of my works of fantasy it makes quite a difference (though not all). This was usually attributable to the societies in which these characters exist having strongly defined gender roles. So, that's a predictable and fairly boring finding.
The fun part came in when I specifically took a look at the main characters where A) the society had enough gender equality to shrug at the flip and B) the character was dear to me, personally, for some reason. There exists a particular fantasy doorstopper series I eventually want to write with a pair of main characters whose character arcs complement and comment on each other. I took the one I liked best and tried this little game.
It definitely caused some differences. Various characters interactions would need to change, and at least one would be probably more complicated. At least two romantic subplots would change because the significant other of those relationships would have to be flipped (well, I guess I could make the MC bisexual or homosexual, which choice would have additional consequences).
The end result of all this was my realization (which will no doubt seem rather banal to most people) that pretty much every consequence of changing these details about a character sprang from how their society would view it. There is, of course, nothing intrinsic about a woman that makes her less fit for practically any task. The only possible exception is melee combat, when having a great deal of muscle mass comes in handy - but of course, there are plenty of very strong women (and plenty of martial roles which don't place so much emphasis on brute strength), so that's out as well. Same goes for homosexuals, especially concerning the romantic involvements. I've seen nothing to suggest there is some intrinsic difference, emotion-wise, between heterosexual and homosexual relationships.
What does all this mean? Well, it means that ideally a reader should identify no less with a hero of the opposite gender or a different sexuality than they would with a hero who is "like them" in these respects. The range of human reaction and emotion has no such boundaries.
That is, in an ideal world. In more realistic terms, given two heroes A and B of which A is a woman and B a man (and sure, a third hero C which is transgender), a male reader might identify more with a male character simply because he assumes the female experience is different - even if every other aspect of their story is identical.
I suppose that could be one of the benefits of well-written fiction that is aware of such issues - it will instill such awareness in the readers. Does that mean I have the guts to actually change the gender or sexuality of any of these characters? I suppose that remains to be seen.