I think I am leaning toward KK starting and moving Kaitlin to the bench. My reason is more based on thinking Kaitlin might be more effective with the second unit. Kaitlin's transition from more of a 1/2, or score first PG to a pass first PG who may be the 4th or 5th offensive option, has been difficult for her.
It was logical to expect her volume of scoring to decrease, but with greater efficiency, and her assists to increase. Some of that has happened, but her volume of scoring has really fallen off a cliff, and her greater emphasis on assists has resulted in far more turnovers than expected. Her offense at Princeton was more creating her own midrange shot than getting open for a 3 pointer for example.
What I am saying is that she appears to be a better 1/2 or shoot first PG than a pure pass first PG, and those skills might fit better on a second unit that doesn't have Paige, Azzi and Sarah as scoring options, whereas KK as a defender/passer is a better fit with the rest of the starters. You could also make the case that KK has just been a better player overall, significantly so over the last half dozen games or so.