Well, flashbacks are always tricky, especially a pre-pilot flashback episode. Usually, they show bad wigs, bangs and mostly tell the story we already know.
But, "The Good Wife" did it very well. It made it into a character study. It showed how Alicia perceives herself. About what she's done and where she wants to go. And with all the back and forth between the telephone conversations and flashbacks, it takes a lot of skill to make those transitions as seamless as they did. This is easily the best show on any broadcast network. No wonder CBS keeps renewing it despite the poor ratings. It's a prestige show for them.
They repeatedly showed the elevator scene because that moment when Will held the door open kept intruding Alicia's thoughts. Elevator is also the place where they usually flirt.
There are two ways of looking at her recruitment. Will could have seen her as a potential fling. Or he really felt a connection with someone he cared about and admired in college. He might have seen her when every other every other law firm saw her as "The Good Wife" of the disgraced Peter Florrick. All said and done, I don't think Alicia owes Will anything. She did her job well during her tenure at Will & Gardener.