1. June Christy
2. Mel Torme
3. Billie
That #2 is a red herring. I love Torme, but generally dislike male jazz vocalists. Heretic as is may seem Rushing, Joe Williams, Jon Hendricks, Johnny Hartman, Leon Thomas, whoever...they drive me nuts. Though I do like Chet, and certainly Teagarden and Louis.
3 is tough, though. I love Rene Marie, Chris Connor, Helen Forrest, Peggy Lee, Anita O'Day, Betty Carter.