My favorite human was David. For many years, he provided a lot of energetic comedy, great singing, and the message that you could be cool and hip without being mean to others who aren't. Even when the late actor (Northern Calloway) became sick and overweight, he kept the character going as best he could to the end.
I know there were some scandals in the actor's life, but that's just a reminder that the people who perform Sesame Street are human and can be as troubled as the rest of us. The trick is that, in spite of reality, they put on an excellent show to educate and entertain children and adults.
Mr. Hooper (Will Lee) runs a close second as my favorite human, but there was good closure to his death and David seemed to keep Mr. Hooper's memory alive. It's interesting that after David was gone, they seemed to give up on preserving the show's essence. JMO