It's also a thing they need to make happen for single player games. The party is supposed to round each other out. The Face leads and the Muscle backs them up if somebody needs to be intimidated.
Indeed. I like to do the dialogue as MY character because that is what I am playing, but he's got 8 charisma because he's supposed to be a rude and off-putting man. If I could initiate convos as him and then maybe call Wyll over to do the actual dialogue checks that'd help a ton. It is more or less how DnD works. If you're talking with someone and decide you need to persuade this NPC you call over your friend and go "You talk to the man" and they'll start doing the social checks you couldn't.
I think just having character portraits in the left would suffice. You click one and the speaker steps back and the new character steps forward. Then the dialogue options change to whatever are available to that specific person.