I didn't mean to imply that WRE would be built as it was conceived in the 1970s. But that combining new boat ride technology (such as that being used for the new Pirates ride in Shanghai), with a western themed experience would be a great way to add a people eating expansion to Frontierland, as well as opening up crowd space if a similarly themed "plaza" was added. With movies like True Grit and other westerns which have been conservatively sprinkled into theaters over the past fifteen years, (often with Academy Award winning results), I think that the western theme is even more relevant today than the pirate theme.
When they were pitching the idea of Johnny Depp pirates movie to Disney, a lot in Hollywood felt that the whole pirate genre was finished. I think the lesson of pirates was that if a film is based on an older genre, and if it is done well, it can succeed.
I think that the Lone Ranger will have a lot of appeal for today's audiences as it won't replicate the stereotypes of past spaghetti westerns concerning Native Americans, and will have appeal for general audiences as the western part of the United States is booming and presumably this brings with it increased interest in the history of the Old West.
Frontierland doesn't have a lot of big attractions when compared to New Orleans Square, and there's not the storytelling that you have in other areas of the park, though the Mark Twain's narration provides some background to the land. Big Thunder certainly has thematic elements, but any specific story is lost on most guests, IMHO, so I think a western themed boat ride would work.
Plus, Pixar is coming out with a Dia de los muertos film. I always thought that this holiday could be incorporated into a western themed river ride in Disneyland, or expansion of Frontierland. Certainly, if they build a plaza with Mexican influence, it could be easily decorated for Halloween and/or Dia de los muertos. I've lived in Central America, and there is a lot of neat colonial style architecture around there which everyday reminded me of a blend of Adventureland and Frontierland. I think a blending of spanish colonial architecture and old westy Knott's style architecture (which no doubt occurred in the old west of california/southern arizona), would be quite a feat to pull off, but could really add something interesting to Frontierland.
Here's Antigua Guatemala where I lived, absolutely beautiful,