I don't understand the whole "bad vs good" debate concerning companions. Since most are origins, I believe that they can be either very nice persons or complete psychopaths depending on player actions. I don't think they will be railroaded into a set path. So having a "good" party will be entierly dependant on how you play the game.
Usually, I'm not much interested in playing origin characters, but in BG3, I could imagine playing as one (after playing my own characters, that is), this could be interesting. I don't think they will be railroaded into a set path, either.
For this reason, I think that maybe the "companion-versions" of these characters could also take different paths, depending on our actions and interactions with them - I'd like that. Maybe to a degree, most likely they won't have a complete change of heart - but who knows?
I'm very curious how many different paths are possible in this game. But I am sure the replayability is high enough to keep me busy for another couple of years 😄