I will also say that I disagree with the 'less but better quality' and 'more but lower quality' crowds. I am more in the camp of 'more with high quality'.
I would personally do this by cutting out the origin stories all together. But that is because I have no interest in them. I imagine Larian has to have metrics on how many people played an original character vs. an origin character (does anyone have this data? Maybe it was insanely popular).
But if they cut out the ability to actually play as them it seems like it would cut the amount of work related to companions down exponentially and let them add a higher number of them to their games.
I also think that they could make the companions more unique and interesting because they wouldn't have to share your plight (they wouldn't have to be sourced collared or tadpole brained).
One could share your plight and want to get to the bottom of it with you. One could genuinely like you and just want to help you. One could be an old friend you run into again from the prologue or whatever. One could be righteous and want to figure out what is going on. One could just need to get to Baldur's Gate and feels safest going with you after your proved you are the big strong. One could be naive and you could convince them to join you on your quest. One could see you as a hero and want to tag along to witness/write about your story. One could be a doctor wanting to study the effects of the tadpole and what is happening to you. One could be evil and want to find those behind this and join them. One could feel a debt to you for saving their town, loved ones or whatever. One could be power hungry and you could promise them big things if they join you.
There are a lot of possibilities that would add a lot of variety - those are just random goofy things off of the top of my head.
There is only so much dev time and so much they can realistically do. I'd rather they work on more of them and cut out the ability to play as them.
