Are you talking about BG3 or DOS2?
Cuz in BG3 we already can see how companions communicate with each other, they argue in plot points, they may complain to you if you do something that they do not approve, and they will leave if you do not listen to this warning.
I think these are already good changes.
I think the reason we didn't have this in DOS2 is because we only had 3 companions, and everyone else was dying. So it was important that no matter what, they didn't leave us.
