I actually like the DOS2 party members. My issue with them is that there's literally no party banter between them at all (you will not see party members talking to each other at all, they only really talk to the designated player character. They will only comment as a group and tell you what they would personally do before you make a major choice). BG3 isn't quite that much better yet, but my standards in this department are also admittedly very high, almost unrealistically so, with how lively WotR's cast of party members are.
This...this right here, is one of my biggest hangups. I love party banter and convos. I desperately want the BG3 characters to interact more and share their opinions together as a party, not just one v one with the MC. Some scenes make sense as one v one but some should definitely be party interaction. One thing that makes D&D what it is has to do with party members getting closer, becoming friends as one cohesive unit.
