Great director's ascent films

An ascent film is a concept I think about occasionally that describes a certain kind of film. The film on the cusp before a great director's most important work begins. Essentially their first break-through movie, usually good but not great, often black and white, often experimental, often dealing with the subject matter of youth or breaking free from a familiar for familial mold. The film they've been trying to get out their whole lives. About a 3.5/5, very good yet not great. Here are examples: 

 Bunuel - Los Olvidados

Tarkovsky - My Name is Ivan 

Wim Wenders - Alice in the Cities 

Scorsese - Alice Doesn't Live Here Anymore (according to Ebert)

Kevin Smith - Clerks (look he had one good film or two)

Bergman - Smiles of a Summer Night

Fellini - I Vitelloni

Varda - Cleo From 5 to 7*

Aronofsky - Pi

Truffaut - The 400 Blows*

Kurosawa - No Regrets For Our Youth (later followed by Drunken Angel, Mifune's first and criminally underrated) 

 Denis Villeneuve - Polytechnique 

The Ascent (oddly enough, her last film spoke to tremendous potential)

*actually great™

I don't know. Just something that crosses the mind.