It was a blast to watch Saul Goodman in action before we knew who Jimmy was, but it would be equally damaging to watch Kim pulling off Jimmy’s ambiguous-at-best moves after seeing her crush things from the protagonist side.
To Rhea Seehorn’s point, as sad as it would be to experience Kim’s death in Season 5 or beyond, it would probably be far more troublesome to watch her stick with Jimmy until the point when her moral fortitude devolved and shrunk to the size of a thumbtack.