I remember hearing a rumor that Leia’s role in Ep9 would be to beckon Kylo Ren back to the light side of the force, that she would be his path to redemption.
With Carrie Fischer having left us, I wonder how it would work to still have that point be the thematic core of his arc, but to focus on her absence. At the end of TLJ, Kylo Ren is left empty and alone with a great deal of power. He decided to spare Leia from death when he had the chance early in the film, and the act of Rey closing the Falcon door on him to me spoke a message something to the effect of, “You are captive to the decisions you make, and you cannot count on others to hold out hope for you forever; there is a point at which it is too late.”

What if Ep9’s story related to Kylo Ren explores that idea? Part of Kylo assumed that Leia being alive would always allow for an “out,” but now she is gone and he is totally alone and self-absorbed. It could be a way to address Leia’s real-life absence in a thematically meaningful way, whether he is redeemed and/or dies or not.