Also 're Annie and her popularity (which is understandable as she is pretty fun), I can't help but notice that the girls are generally as popular as the amount of screen time they've had with the MC. Probs a concidence but I thought it intriguing none the less.
Seems pretty self-explanatory to me. They're all so well crafted that the more we know them, the more we love them
More seriously, I think that attraction for Annie comes primarily from the fact that her model feels really new compared to the other. We may have seen in other games Chris or Sarah lookalikes, but Annie simply pops out. Combined that to her stellar personality, and you've got yourself a winner