I had a sneaky suspicion about Julia. She saved Homer and Marge from the mobbing fans, but she wanted something in return. To be president of the fan club seemed a bit weird.
So after the opera, Homer is going to retire. He says he can think of other things to do on his back, then they cut to him painting on the Simpsons ceiling. He's replicating one of Michelangelo's works of art, but is substituting the family merabers.