I did a dry-run of this challenge and in the end I took Aspirations and Traits into consideration. Everyone plays different so I left it up to interpretation. In the end I'm going to use a range of things to make the decision. How the girls parties go, who made the most friends, who did the prince roll the most wants for and who do I think is ultimately the right one.
I the dry run I was very strict. The girl who performed the best one (highest medal at the party and highest relationship with the prince and other girls.)