I love coming up with historical variations on characters. I've come up with a Victorian Miho Tohya and a Renaissance Death from Sandman
. I've also got an idea for a Renaissance Black Cat running around my brain, but that one wouldn't be cheap. Heck, I'm planning to do Gaz Membrane in her 20's. She's going to be wearing a more grown-up version of her outfit and be busy with her cell phone all the time.
Having the big defining characteristics there the main thing. Then you can go and have a ton of fun!