Playing the same game again only from the perspective of one of your companions or are these total different stories? Do i get some kind of bonus when i am going to play the origin characters first or is this just an optional gameplay?
However i´m going to play my own custom character for sure. That's the basic idea of a pen & paper game: slip into any character you want to be. I don't like it when you have to hatch pre-made characters like in Dragon Age.
A pity that Swen doesn´t showed in the presentation the face / body customization options. I´m looking forward to them. I also hope for different voice options like in the Baldur Gates or Icewind Dale games.
What I am generally very critical of is that there are no plans for localization of the speech according to the Steam site. The games had localized the language over 20 years ago and should be standard by 2020.
No, they are companions like you would meet along the way in Baldur's Gate. You just have the option to be one of them if you wish. Otherwise, you can create your own character.
I think it would have been fun to play Imogen in BG1. "Hey ya!"