When American Adventure first opened, it was basically variations on a Wild West theme, which you could argue was too narrow. They did try to broaden things out with Space Port, but by the time they did this area, they were already scaling back their budgets, and didn't have much money left for theming. I actually think that America would be a really good theme for a park: a Mardi Gras New Orleans area, a Hollywood area, a 1920s gangster Chicago area, maybe a San Francisco area with an Alcatraz attraction. I don't know if there ever has been a really good American themed park though. The Wild West stuff at Knott's Berry Farm is incredible. I'm not sure if the other areas have lived up to it, although the re-themed Mexican area could be really good. California Adventure was very good, albeit themed to one state. It was just too small at the start, and now it's bigger they'ved diluted the theme with things like Pixar Pier.