Jonathan, I CANNOT believe you left out Sergio Leone's "The Good, the Bad and the Ugly", maybe the greatest western ever made. Have you not seen this movie?
Of course I've seen The Good, the Bad, and the Ugly. But I have to be honest: I never thought Leone's Westerns (or any of the spaghetti Westerns, with the exception of the Yojimbo-remake A Fistful of Dollars) were any good. Those interminable ten-hour takes, the terribly hammy acting, the depthless stereotyped characters, and soullessly contrived plots--to me they always seemed like cheesy parodies of the real thing, like General Garcia's gallery of velvet paintings compared to MOMA.
Sorry, but that's how I see them.
I alwaysd found it funny that Westerns are so formulaic and sometimes that formula makes a terrible film and sometimes it's great.
What you said isn't just true of Westerns. Every genre film (mystery, thriller, bedroom farce, sci-fi, horror, etc.) can end up "formulaic." After all, they generally evolve from the same situations and use the same kinds of character, which is their charm and their challenge. It ain't the ingredients; it's the way they're combined that gives a genre flick its distinctive flavor.