Quote Originally Posted by coeruleum View Post
People tend to have more than one facial expression though. I feel like a lot of these could be the same person at different times. Others, clearly not (like the High vs. Low Agreeableness males.)
It's possible. Imo there's a baseline facial expression that tends to represent a person's character pretty well. That baseline expression will change according to different situations and emotions, but even the way they react to those situations tends to fit with that character baseline.

The high openness eyes are one example of a facial trait I tend to see people either having consistently, or not having.

Also each of those composites were groups of people that had one particular trait especially low or high. Real-life people would probably show signs of all 5 traits (either high or low) - except the ones they're neutral on.