It's never been close to an E ticket ride. It was really an opportunity to take advantage of the popularity of TS while offering a Space theme ride to Tomorrow Land. It's more that run it's course. It's barely "shall do ride" and more of "may do ride" for guests, rarely appealing to children over the age of 10, and known for it's very short wait times.
WALL-E, on the other hand has much more promise to offer more exiting technical appeal. With 3D, Imagineers could really offer a spectacular ride. Interactive and innovative.