Mia suddenly abandoning her date with Greg to go meet Sebastian at Rebel Without a Cause. What's the thing that really convinced her to get up and leave? Hearing jazz music playing at the restaurant that she had previously told Sebastian people talk over without a care in the world.
Sebastian slowly holding Mia's hand as they watch the movie, complete with their Almost Kiss at the end.
A small one: after walking for a long time watching Mia trying to find her car and claiming his is parked further up, it's revealed that Sebastian's car was in fact parked opposite the house they were at. Maybe he wanted to walk her to her car; maybe he wanted to talk to her more; maybe he wanted to look at the view with her. Either way, it's a sweet reveal.
During their big argument, Sebastian accuses Mia of hating jazz, a claim she makes shortly after they first meet. She angrily retorts, "I do love jazz now! Because of you!", showing how much of a positive change each has had on the other.
After Mia's show supposedly tanks, Sebastian gets a call from a producer wanting to get a hold of her and drives all the way to her house to tell her. He introduces his presence by loudly honking outside her house like he did back when they had just started dating, and tells her he'll be back at eight in the morning to drive her to her audition whether she decided to go or not.
Earlier in the film, Mia casually mentions that she lives in the house across the street from the library. Sebastian remembers.
The first time Sebastian sings "City of Stars," he slowly dances with an older lady before her husband nudges him off, annoyed. When he continues to sing, they happily dance in the background.
When Sebastian finally opens his club it is named Seb's with a musical note in place of an apostrophe, like Mia had suggested instead of Chicken On A Stick.
It's a small one but when Mia's show doesn't go over well, you can see her three roomates cheering her on. True Companions indeed.
The fact that La La Land is the first movie shot on 35mm film to win Best Cinematography since Inception.
Damien Chazelle is the youngest director to ever win the Oscar for Best Director. All his hard work paid off.
Callie Hernandez, who plays Mia's roomate Kate (the one in the red dress), said in interviews that before this film and Blair Witch she spent a few years living on her friends couch because didn't have a lot of money and mostly played cello in bands. Fast foward to 2016 and she's part of a critically-acclaimed film that was nominated for Best Picture and has parts in Alien: Covenant and Under the Silver Lake. Talk about Rags to Riches.