Allowing a choice of gender would involve doubling much of the dialog, artwork, etc. Choice is good, but I wouldn't want to sacrifice on plot or quests, etc, to get that in.
You're the Commander of an army plotting to become absolute ruler of the country. Because of that, I think most of the dialogue would be gender neutral (since it would mostly deal with politics and tactics and whatnot), so it'd hardly be 'doubling', especially if the PC doesn't actually speak out loud, but only has written lines.
As for doubling the artwork... well, the artwork PC, certainly. Everybody else? Well, the princes and princesses maybe.
It would be more work, certainly. But I don't think it would double much of it.
