Off the top of my head the top echelon of dancers, IMHO, would include Cyd Charisse, Ann Miller, Eleanor Powell, Vera Ellen, Leslie Caron, Shirley McClaine. If any of them are dancing, I drop what I'm doing and watch. There are lots of good dancers, but when you watch, they were really good at being lifted, in keeping time, in moving with the music. Even of the dancers I listed here, Charisse is still the top, an artiste. Vera Ellen did some of those sspecialty dances also, but in fewer films. I loved films with Ginger Rogers, Betty Grable, and Mitzi Gaynor, but I don't think they had the training or range the others did. Doris Day was a very good dancer, and started in ballet, but tended to focus more on the singing. Charisse transcended the music and was the "go to" dancer for most of those specialty routines in the movies. (This list is not exhaustive, but I can't think of anyone who was equal to Charisse)

SRS