For Lando, maybe it’s possible to increase his presence in the film by using his voice in some places (offscreen, over radio etc) from his large body of radio plays and voice acting for games.

Billy Dee Williams voiced Lando in all of the following:

Star Wars Episode V: The Empire Strikes Back radio adaptation
Dark Empire audio drama
Star Wars: Jedi Knight II: Jedi Outcast
Star Wars Rebels series
Star Wars Battlefront
Star Wars Battlefront I

That way his limited screen time will be made up for a little bit? Thoughts?