Hi! First, I'd like to say that this topic is amazing. Only great suggestions, and I hope Larian sees this!
I suggest that we need a way to see who is observing our dialogues or scenes.
When I'm playing with other people, we constantly need to check if everybody is following the dialogue. Maybe a small icon on the bottom left with the player's name. So, whoever is engaging in the conversation knows that everyone at the party is watching, or at least people who are interested, and can progress the dialogue instead of constantly asking, "Are you guys watching this?""I'm talking to Shadowheart, okay?"
The option to automatically join would also be a solution, but I think one thing does not exclude the other. Since you can join, exit, and rejoin.