"I think people will have to get used to this bunch. I'm not convinced there'll be many more companions, if there's any at all. Consider that D:OS2 had you meet everyone initially, much like BG3 has done. Unless Larian has been running an extremely long game of only previewing the party members they'd show off in EA, I wouldn't hold out hope for another four or five party members. I feel like we might get one or two, but I don't think we'll get one for each class, nor get more than one for any class."

Larian said before EA's release that they will add more companions later (even in the EA), they opted for more "evil" ones at start to encourage us to try out playing evil characters, as people generally play good characters in the game. I agree half of them seem to be of a pretty good alignment though.