It's amazing how much this film is revered and how much greatness is in it. John Wayne's performance is fantastic (he paints Ethan as a very flawed character - both protagonist and villain at different points), the photography here is breathtaking and its on-location view is probably only rivaled by that of Lawrence of Arabia, and the story with it's ensconced themes make it a subtly resonating story.
The less than par acting and comic relief seem to all fit into the genre niche aspect. While it's a bit frustrating with so many other great things going on here, it fits. They're stereotypes of the genre that have been accepted and are loved along with the rest of the film.
The two finest scenes in my mind are 1) A sequence early on in the film where we see Mrs. Edwards pull out and hold close a Ranger's uniform when the the newly arrived Ethan, Mr. Edwards, and Marty are hired to go out look for some cows the Comanches released. There is so much emotion, so much meaning, so many unsaid things (danger, sadness, love, etc.) in a scene with no dialogue and the quiet movement of the camera allows us to take this all in. It's heartbreaking. AND 2) The iconic last shot where the doorway motif's final use shows the door close on Ethan as he walks away from Debbie, Marty and the Jorgensens inside their house. Their new era has begun, but he doesn't really have a new era to begin. Searching for Debbie was just another chapter in his life and he's on to find his next one. He never settles.
While I don't love it (more often than not when it comes to Westerns), not even close, it's an undeniable film. Probably Ford's theoretical best in a long line of great films.