I think if it had been Edith, it might've made it too obvious to Kirk too early what was going on. (Although the novelization asserts that he did revisit Edith, Carol, and other people from his past, and that Picard just happened to show up while he was in an Antonia fantasy instead of one of the others.)
Carol, maybe (though I never liked Bibi Besch much), but I never really thought that Gillian was interested in Kirk. It seemed to me (though maybe the novelization is coloring my recollection) that whatever flirtation he attempted with her pretty much bombed, either because she was too focused on the whales to be interested in romance or because he was a couple of decades too old for her. Yeah, she did kiss him goodbye at the end, but it felt more like a friendly gesture than a burgeoning love affair.
Me, I would have just mentioned "Carol" or "Gillian," neither of whom we were ever likely to see again anyway and whom don't require a lot of exposition. If audiences recognized the names from the earlier movies, cool. If not, no harm done.
Carol, maybe (though I never liked Bibi Besch much), but I never really thought that Gillian was interested in Kirk. It seemed to me (though maybe the novelization is coloring my recollection) that whatever flirtation he attempted with her pretty much bombed, either because she was too focused on the whales to be interested in romance or because he was a couple of decades too old for her. Yeah, she did kiss him goodbye at the end, but it felt more like a friendly gesture than a burgeoning love affair.