I always enjoyed Carvey’s George H.W. Bush impression. It was funny without being contemptuous of Bush. I saw an interview with Norm MacDonald once and he claimed that the key to a successful impression is having some affection for the person you are impersonating. For this reason, he didn’t like Alec Baldwin’s Trump impression, because Baldwin was too obviously expressing his contempt for Trump. He believed that Baldwin’s contempt ruined the impression and made it not funny. I found MacDonald’s take very interesting.
I liked Norm’s Bob Dole imitation, and I know he and Bob met each other with Norm in his Dole makeup.