I liked Mission Hill, it had a sort of weird charm to it. And at least you could catch it in reruns on Adult Swim, when they weren't decided to fill in gaps in their schedule with other networks' leavings like "Baby Blues".
If you listen to the DVD commentary they had so much shit planned out for this show that they never got to do, it's a same shame because they had years of material already built up.
I loved the "Plan Nine from Outer Space" episode. Though the younger brother got to the point of being kill worthy in every episode without ever dying.