Planet Sheen is a good example of Scooby and Shaggying. They took the funniest character from the show, and he's unable to hold a show by himself. You miss all the other funny characters (like Jimmy's innuendo fountain of a father), and you lose what made Sheen Unique and funny. I don't see why anyone even likes it. How come Carscratch got such a cold shoulder, and Sheen's show, which no one really likes is still on.
Come to think of it, the only cartoon I can think of that's universally hated was Allen Gregory. THAT was a terrible show considering those behind it. Everyone was either an oblivious jerk or a vengeful jerk.