I am not sure if you are advocating to cut Mr. Johnson or not. When I first read it I though - yes he is. Then I read it two more times and the tone seemed different and I thought no he isn't. And then...long story short (too late) I think Mr. Johnson is an important supporting character to have around as he can play the straight man to every character on the show. He can be frustrated by Grover (clearly), The Count, Herry, Ernie, Alan etc etc. I am not interested in them expanding his role and I am fine if a season or two goes by without seeing him, but he is comedy gold when used well. I associate him with character actor Gale Gordon who appeared (sometimes minor/sometimes major) in roles in the various Lucille Ball shows. Always flustered by Lucy's antics. No one on Sesame Street does flustered better than Mr. Johnson.