Currently, they're to show where the girl starts with a decent skill bonus (this matters a little more in a mode where you can't just set a girl's popularity to 100.)
There are future things this will interact with/be required for as well. For now though, it's free stats, and helps differentiate girls and give you an idea her strengths.
Please remember that classes are a placeholder mechanic for something similar and complicated down the road, and that it's mostly there to help Normal Mode interact with traits. Scramble Mode, on the other hand, has the tradeoff that you cannot just get a cheap girl with stupid levels of stats, you always have to pay for her, one way or another. It doesn't need a traits or catchup mechanic for a girl in the same way. But that said, 10 stats for each skill is 10 stats, that's nothing to sneeze at and can make a big difference in your rep/inf economy (which are considerably more important now)
On the flipside though, I'm not content with the Eager Learner trait, or the Hustle Queen trait, and I'll be looking for ways to give them more upside in the near future.