I like the Western idea, mostly the modern Western idea. I'm inspired by "The Postman" movie. It's set in post-apocalyptic America and everyone goes back into a Western-style society.
As for characters, I picture myself as a gunslinger girl of a different ethnicity (if it's a modern western, then the country's already diverse). She's one who knows how to handle a gun (pistol, shotgun, etc.) or any weapon available (katanas, anyone?) and can stand up to a man in a duel.
The whole katana idea is pushing it though. It's optional.