I'm always looking for the ripple effects down the line, so I don't thing there's anything I always do, I've even got a Sage save telling Josy about Chad and Troy but not telling Sage, that could be a fun conversation when Josy slips up and Sage finds out.
Yeah, Quinn definitely wants to run the HOT sorority herself, and it's shown several times in game that a lot of the girls are blaming Sage for Quinn's shitty decisions, I think Heather says something about how being a senior is getting to her, and that she should consider stepping down.
I think how you handle the Chad-Troy revelation in regards to telling Sage is going to have a large effect, she's already highly volatile, she confronts Mel and Sarah in quite a hostile fashion if you don't tell Sage about it, so I think that it can end up being a deciding factor if you've told Josy, there might be a scene where Josy slips up and talks about it, Sage finds out and starts coming down hard on her, things escalate and Sage is basically requested to step down as the president of the HOT sorority because of her inability to keep her shit together.
At the same time, I think how you deal with Riona during the Halloween party is going to affect her role in Quinn's operations, if you make out with her (on an others run) or if you give the neutral response on a relationship run, I think she's going to be motivated to start distancing herself from the prostitution and drug dealing. At the same time, it's interesting to see the developing dynamic between Quinn and Lily, it would not surprise me if Quinn actually comes involved Lily in her drug dealing directly, as for the prostitution, well Lily is already aware of it because of Mona, and it's not clear if Lily is playing tricks for clients at the Pink Rose like many of the other strippers seem to be.