Ideas developed by everyday fans are fun, but it's sad to see the ideas that made it pretty deep into the planning stages that never made it off the drawing board so to speak. Frontierland was supposed to be Thunder Mesa with a coaster that mixed the ride design of Everest with backwards rolling sections and AA figures with the theme of Big Thunder Mountain, as well as a themed flume ride, well before Splash Mountain. A part of that ride-that-never-was was used in World of Motion's stagecoach scene. Also, Villain Mountain as mentioned above along with Fire Mountain for Adventureland, both supposed to be big new E-Tickets for WDW's Magic Kingdom. Plus all of the countries for World Showcase that never made it like Equatorial Africa, which ended up as that quasi-African themed Outpost, Spain, Russia, Switzerland, Israel etc. or Japan's Mount Fuji rollercoaster that all were planned but never conceived for political and financial reasons
I still think they should tear out the Tomorrowland Speed Way or Race Way or whatever it's called and make better use of all of that space. It's be the perfect place for some kind of more handicapped accessible, less financially unreasonable 20.000 Leagus ride. After all it's the area that connects Fantasyland and Tomorrowland. It wouldn't have to be an actual sub ride, although that was so cool, but something that would atleast give the riders the feel of a liquid space adventure.