I have to disagree, the stars are triggered by the story, and having them prevents you from doing things out of order because you cheated your stats too high. The problem I see is that certain events will not trigger if the stats are too high. There should be a minimum, but not a maximum, that way if someone cheats their stats, the stars are the only factor left to trigger an event. It can work without the stars, as long as there is still some other trigger besides the stats, but they were a nice reminder of how far you were into her story.
The other issue is that almost everyone's story is tied to everyone else's. It makes sense for Amy's to be tied to Veronica's, and Sophie's to be tied to Ashley, for example, but having the main three linked can cause issues, especially if someone doesn't want to pursue every one, or just doesn't want to do them all at once (some like to focus on one at a time).