Actually, I wonder if Simpsons might benefit from a time jump. Start a new season and everybody's seven years older, Bart and Lisa are in high school, Maggie's 8 and going to Lisa's old school, but she's very different from Lisa somehow...I don't know. I think it'd be interesting. Are there really so many stories left to tell with the kids at ages 1, 8, and 10?
I gotta say though, the way The Simpsons stays stubbornly frozen in time is REALLY WEIRD sometimes. I remember one episode a couple years ago where they cut to "THREE YEARS LATER" just as a gag, and Maggie is STILL A BABY! IN THE SAME EPISODE!