There are quite a few celebs we didn't cover yet: Pocahontas (though being pacifist and from the East coast she might not count), Big Nose Kate, Billie the Kid, Butch Cassidy & Sundance Kid, Black Bart the rhyming robber, the Dalton Gang, Buckshot rogers, Johnny Ringo etc.
Then there was that woman who lived as a trapper and they found out her gender only when she had died - I can't recall her name.
And how about the real and fake Native Americans? Grey Owl (fake), Tecumseh (genuine), Seattle (prophetic) etc?
And since we have Sitting Bull, how about Custer? Davy Crockett? Daniel Boone?
Nice list. Locutus of Bored did a Billy the Kid one, though. Not saying I won't allow another one, but with so many great options left, why would anyone'd risk splitting the vote?!
And, no, Pocahontas doesn't count.