For consistency of vision the award would have to go to either Buñuel who, despite having to do "hack jobs" to put food on the table, never abandoned his surrealist principles or Stanley kubrick who never made a bad film and forever remained the sad, impish misanthrope that really CARED about humanity (I mean he cared for his characters despite his better judgment).

BUT....Orson Welles and Jean Renoir are the giants for me.  Their films touch me so deeply and engage me on such a deep intelectual level that I can conjure up any of their films at will and replay them in my head.