WDW has several "grown up" attractions such as the
Carrousel of Progress, Great Movie Ride,
Kilimanjaro Safaris, Soarin', and Spaceship Earth. I'm saying the World Showcase is the most "grown up" area at the theme parks. The WS was designed to be what it is and, all things considered, might very well be the one area in the four parks that remains closest to its original opening day vision.
Going one step further, I'm saying let's fix the attractions at MK
and DHS
and DAK
and Future World
before we go messing around with the World Showcase's vision.
WS still could use a few more countries though.