I just recently finished my first playthrough.

Spoiler:
I got the ending where Ethan, Madison and Shaun get a house together. I thought their relationship bloomed fairly fast. But I guess maybe they connected because they went through a very traumatic experience together?

I killed Jayden in the car yard. That was a silly mistake on my behalf and I wish I didn't. So at the end Shelby was chasing Madison and Ethan killed him. I got to see Carter put on the ARI glasses.

Oh, I left Lauren to die in the car when it was under water as well. So I had nothing with her after that.

I think they are my main differences.