So, I have an idea that I think might allow for side stepping the hard coding potentially for the people we have for our party.
I myself have tried to mod this game, and i don't have the attention span for it.
so the request would be a way to add both disciple / handmaiden as switchable party members by having the security console aboard the ebon hawk just switch which one has the active spot on the party screen, so when you leave the ebon hawk, you can essentially activate/deactivate one or the other as a person who can be a party member.
A potentially more advanced version cold allow for the player to deactivate a party member and make their slot open to have another party member active.
IDK if this would be possible, I realize the hard coding might prevent it, I just thought this might be a potentially viable sidestep, and i haven't heard anyone talk about it i don't think, except once on lucasforums before that died and i didn't remember if there was a definitive yes or no.