Which of Jack's girlfriends actually seemed like a good match?

So he ends up with Vicki, who had the personality of a cantaloupe. Which of his girlfriends (apart from his roommates) would have been good for him?

Barbara, from "The Older Woman," was probably the most intelligent and centered fling Jack had. The writers seemed to suspect this, so they wrote that both she and Jack knew it was temporary. Otherwise, why would Jack give her up, especially since she likes to surf?