What about Oz? There aren't any Oz-themed villains that I know of, and there's 14 public domain books worth of material to draw on (more, if you want to pay cash for using a Ruth Plumly Thompson reference). For that matter, what about the Robin Hood or Arthurian mythoses? (Is that a term?) It's a shame Roald Dahl's stuff is still under copyright - a Dahl-themed villain would make for some splendidly gruesome stories.