While I love the idea of using Indians, which would be awesome. The thing that attracted me to Malifaux was the cowboys and there haven't been any new ones really. And with so much you could base on history, I think the Freikorps are based on the Pinkertons, with that in mind I'd really like to see version of real people. Billy the Kid or the James brothers for the outcasts, Wyatt Earp for the guild, Davy Crockett or Daniel Boon for the Arcanists, hell even a John Wayne or Clint Eastwood riff would be great. Going a step or two to the side a version of the Lone Ranger and Tonto or Zorro, American Tall tales of Paul Bunyan, Pecos Bill, or John Henry. Heck Johnny Appleseed would make a tremendous Arcanist bringing plants to life to punish people for destroying the land.
I also wouldn't mind seeing the story advance and maybe promote some existing models, Francisco gets his own grew. Rusty Alice strikes out on her own...
And of course a circus or carnival crew would be spectacular.