All of the points here are great, i'm on the "pls don't team" but i think there are ways this might partially work.
First of all, we do not know for sure how long Act 1 will be, will the scuffle at the towers be a beginning of Act 2, or the finale of Act 1 (which i hope for). In either case, i think it would be great, that after the tadpoles are removed, you get to keep the people that have high opinion of you, and the ones that you didn't got along with just go their way (Like, Shadowheart goes on with her quest, Astarion goes to Baldur's Gate and so on). It wouldn't be too OP since every decision comes with someone liking it and someone that do not. So there won't be a possibility to keep all of the people - someone will surely go away. I really hope they won't force us to chose by ourselves at the end of the act/story arc, because it doesn't make sense for DnD. In DOS:2 you could basically just scratch the character's skills and start all over, depending on your needs. In DnD it's not possible, so cutting us off so abruptly wouldn't be nice.