I'm pretty sure this can be done, to an extent. Influence is tracked through the npc number in npc.2da, where the slots are 0-11. It's also a constant, rather than a global, which means in order to change slots but keep track of influence, one would have to add the globals and rescript practically the whole game.
Now I'm with you as far as replacing G0-T0 with Handmaiden/Disciple, but having both Hanharr and Mira just doesn't work well for the game. You'd probably have to make do with one or the other. However, I'm pretty sure I remember seeing a script in the game files that assigns the companions to 1 of the 10 party table slots, it would just be a matter of finding it again.
Here's what I suggest (I'm pretty sure I can do this):
I can either make it so you can swap back and forth between Handmaiden/Disciple, or I can make it so one of them takes the place of G0T0, and when you "recruit" G0T0, have it so he's on the ship but not an available party member.
I think I'll try both anyway so people can choose their preferred solution.
Good with dialogues and getting better
Working on Scripting and Module Editing/Re-skinning
Started work on Modeling New Areas