If any fairly obscure characters (like Lew Zeland, Beauregard, or Thog) were used on the show, I wonder if they would be better known today?
After all, it seems like back in the 1970s and 1980s, Bunsen and beaker were just as important characters as Link Hogthrob, Beauregard, Pops, The Swedish Chef, and other of the same kind of characters. They appeared sparringly in the specials from the 1980s (they weren't in John Denver And The Muppets: Rocky Mountain Holiday, and aside from some brief clips, Bunsen didn't appear in The Muppets Go To The Movies, and both characters only had really small roles in the other specials. Also, they didn't have any lines in The Muppets take manhattan, althouhg I have read that they had a scene that was cut from the movie). However, after the deaths of Jim Henson and Richard Hunt (Beakers performer), they were used a lot more, having bigger parts in the movies and being quite major on Muppets Tonight. They hesitated to recast Rowlf and Scooter, who were both more important characters, and many of jerry Nelsons characters were not used much (even though Jerry nelson was still as major of a performer in the 1990s as he was in the 1970s and 1980s).