Dear Jaime: I agree with Sir Bygber that Tarantino is a better writer of dialogue than he is a director or scenario writer. He creates vivid modern comic book-like characters, but they tend to meander, no matter how melodramatic the situation.
Yes, I agree that one great movie can make a great director, especially if forces prevent him/her from doing more. Dryer would be a great director, for instance, purely on the creation of THE PASSION OF JEANNE D'ARC (1927) -- without mentioning VAMPYR, made the year after.
But I don't think Great Directors should be mixed up with commercial trendsetters like C.B. DeMille or James Cameron.
Dorothy Arzner is usually the director mentioned first on the distaff side. She began as an editor and started directing in the late 1920's. THE WILD PARTY (1929) is one of her best in the period. She continued into the 1940's. DANCE GIRL DANCE (1940) is singled out by Hallawell, but I've never seen it, that I can remember.