(in order I encountered/explored them, chronologically)
Orson Welles
Alfred Hitchcock
Woody Allen
Robert Altman
Ingmar Bergman
The guys with the widest, most diverse palettes.
Honorable mentions:
Francis Ford Coppola for the 1st two Godfather films, Apocalypse Now, The Conversation, and Bram Stoker’s Dracula
John Huston, another wide, diverse palette.