What I remember best are three comedians who became well-known, thanks in large part to Allen's show: Don Knotts, Tom Poston and Louis Nye. Those three killed me (and my dad) every time!
In addition, I loved Allen's constant ad-libs and his versatility. He could do about everything, especially write songs (over 7,000!). He must have been very popular in Hollywood, too. Just look at the huge celebrities that came on his program three or more times. It's like a "Who's Who" of show business.
This hour-long program was consistent in entertaining us folks with a good blend of music and comedy - monologues, interviews, skits, etc.
"Genius" is a very overworked word but Allen's case, it fit. He was a true genius in his field of show business. I wonder how many people know that this guy started "The Tonight Show." He was the first host, long before Johnny Carson and Jay Leno.
Better than his intelligence, he was simply a nice guy whom everyone seemed to like and respect.