I can't think of a jazz harpist who swings harder than Dorothy Ashby. To play swinging eighth notes on the harp can't be easy, and Ashby makes it sound effortless. Coltrane doesn't really swing on harp (and that doesn't seem to be her objective), and other harpists, contemporary to Ashby, seem fairly stilted (90 degree angles) in comparison. I haven't heard that Atlantic record posted above, and need to.
I will spin Afro-Harping tonight.