They need to just stick to the material from the books and keep him an anti hero, have him redeem himself from the death of logan and have him sacrifice his life saving someone from his past to complete his character arc that will bring his story full circle!😉👍🏻
I think Mandy would fit better into a redemption arc that will flesh out her backstory completely, where she works alongside Jack bauer to foil a new threat rather than make her another run-of-the-mill villain, due to the fact that she has been trying to get out of the assassin game since DAY ONE and in season 4 she finally got that chance from Jack who despite knowing all she had done, all her crimes which involved poisoning president palmer he willingly helped her get immunity, that right there would bring loads of storytelling potential into the film, with her being the one who breaks Jack out of Russian prison as a means of paying back her debt to him for his part in her getting a second chance at a new life while helping him stop a terrorist threat that has personal implications for them both! 😎😁💯🔥👍🏻