The below is entirely my opinion, so feel free to disagree.
Aubrey can have a pretty big shift in personality, if you go down the solo Girlfriend path. When watching the poly video with Riley, you really see her say she wants something serious to be dedicated just to her. If you stay FWB, there are still changes, but not nearly as big as the GF path. Either way you still become a cornerstone support in her modeling career, it's just a lot more casual as FWB.
Chloe starts off looking really conceited, stuck up, snobby, outside a few key moments. You see a few elements of the "real" her when playing volleyball, stopping by after Grayson punched you, and at the pool. As the election ramps up, the personality kicks into high gear, although if you are on her Girlfriend path you can still see the 'nuggets' underneath it. No matter how the election plays out, she becomes a lot more laid back. If she is your Girlfriend she really gives off a vibe that I have like. Kicks back, plays video games, sets up a hot air balloon trip, and more. In my eye, she uses the dominating personality as a shield in the sorority.
Amber also can undergo a huge shift after the talk with her about the drugs. I think it's the biggest by far if she gets clean. The detective scenes to find Nora we re definitely one of my top favorite scenes. And varies based on the MC personality.
