Romana Vrezhenski is a communist villainess who was for some reason introduced long after the fall of the Soviet Union. Troika is the only story I remember her from, and this was the best image I could come up with, but that big red star on her forehead is permanent. No relation to the Frank Miller villain that many comics readers will remember with the blond flat top haircut and the swastika tattoos on her breasts. Anyway, she teamed with KGBeast and other Soviet-themed villains, demanding a share of Wayne Enterprises' profits or she'd destroy their buildings.
Pros: Bald women with communist tattoos are an underrepresented minority in movies these days.
Cons: Her crime for profit scheme seems to go against the whole communist theme.
How I'd do it: The Soviet Union isn't a very good villain theme anymore, so maybe she could be North Korean, with a picture of Kim Jong-Il stamped on her forehead?
Casting Guesses: Can Sinead O'Connor act? Brigitte Nielsen in her heyday would have been great, but I think she's a crackhead now. Demi Moore (G.I. Jane) and Natalie Portman (V for Vendetta) have gone bald for movie roles already.
After The Scarecrow, Ra's Al Ghul, The Joker, and Two-Face, who should be Batman's next enemy in the Batman Begins/The Dark Knight series? Well, as of now we know that Tom Hardy will play Bane and Anne Hathaway will play Catwoman.
Check out the master list for all the villains covered. I've pretty much run out by now. Obviously, there are more Batman villains, but not any of significance that I know of. As of February 2009, no one is confirmed as a villain. Not the Johnny Depp Riddler, not Phillip Seymour Hoffman Penguin, nobody.