In the spirit of the NCAAs, first four in:
MASH (the Frank Burns years)
Barney Miller (even with cast changes, Fish, Nick, show kept its edge)
Taxi (could do without Latka, Jim saved the show)
Odd Couple (perfectly cast, even the Pidgeon Sisters)
Last four out:
Cheers (the Coach years)
Mary Tyler Moore Show (again, a great cast)
Honeymooners (the 1955-56 run, even while short, set the standard)
Happy Days (until Fonzie moved in the apartment above the garage)
Honorable mention:
Just about anything Norman Lear touched, All in the Family, Good Times, Maude, The Jeffersons