So common motives for murder and how they would apply to this case.
Motive
Drugs-Sure they probably partake in typical college recreational drug use. Smoked a bit of weed most likely. That not likely to lead to this type of crime. Not like they were drug kingpins.
Sex- With attractive women you always have to consider as motive. No sign of rape or sexual assault though. Could be killer who gets sexual thrill out of the kill though.
Money-Broke college kids so not likely they have much cash. But people get killed for what would amount to chump change.
Jealous- Someone was jealous of there popularity and social status. Maybe some incel who was jealous they they had what he did not.
Revenge-They pissed off the wrong person.
Random Serial Thrill / Killer-Ted Bundy type killer. Like when he committed coed murders in Florida
Which motive do you think is more likely? Or another motive you like more?
I'd be careful about using "attractiveness" as a quality that inspires murders or puts women more at risk. Being extroverted and having lots of contacts is a higher risk factor than sitting in the library studying and having few friends, IMO, but both types of women can be attractive. IMO. I think you're referring more to the fact that at least two of the victims had some Instagram content where they presented themselves in a specific way, considered attractive (apparently) by many young men who then followed them (cyberstalking would be a subset of this one).
Sex therefore needs some sub-categories (fetishes; obsessions; sexual sadism; sexual dysfunction such that ordinary sexual performance is lost and violence is now the substitute, etc).
I have some things to add to your list (I am on a Thrill Killer rabbit hole right now, but it's not my top group of hypotheses):
Secrets that might be about to be told that could be life-changing for the person who commits the murders (or persons). I suppose this could be a version of revenge - but in my hypothesis, it's more cover-up than revenge and possibly occurred merely because of fear, rather than retaliation. It's a preventative measure.
Fear of Abandonment/Rejection/Social exclusion. This can include public humiliation, feeling disrespected in one's own social world, etc.
Revenge can be expanded too - angering the wrong person translates into "angering a person with conduct issues and impulse control issues" at the very least - investigators are likely asking the many people they're interviewing about such a person. I like this theory because it's consistent with what I see LE doing (interviewing tons of people, asking for context, and then saying they see "patterns") Naturally, a vaguely antisocial person with no previous criminality (despite previous antisocial behavior) who also has impulse control issues or is known to be aggro would be a prime suspect.
I suspect that more than one of these are at play at the same time, which is one reason it's so hard to figure out what happened (for us and for LE, but I do believe LE has a specific POI in mind).
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