Ann Doran also appeared in a McHale's Navy episode as Captain Binghamton's wife "Pumpkin", just as snooty as she was in Three Sappy People (and a lot older and less attractive, if she ever was).
Speaking of MN, Ensign Parker was a pretty good sidekick to McHale. And I definitely agree about Robin the Boy Blunder and Jefferson Milhouse D'Arcy as top sidekicks.