Number one for me is
The 400 Blows.
Followed by Playtime and
Three Colors: Blue. Two personal favorites are
Read My Lips and
Camille Claudel.
Hardly anybody else on here cares about Playtime, so I'm relieved to see that someone else sees Tati's genius with me!
Didn't know you liked Rohmer, have you seen much else from him?
As for myself, it'd be much easier to do this
Jean-Luc Godard (Pierrot le Fou, 2 or 3 Things I Know About Her)
Eric Rohmer (The Green Ray, and many others)
Jacques Tati (Playtime is by far his masterpiece, but he has several other achievements)
Jacques Demy (The Young Girls of Rochefort, and many others)
Robert Bresson (A Man Escaped, L'Argent)
Jean Vigo (L'Atalante, Zero for Conduct)
Jacques Rivette once I see more of his films
A little New Wavey but that's okay