I prefer making my own characters too, which is the reason, I haven't played Disco Elysium or Witcher yet, despite liking Geralt in the books. I like developing my characters and back stories.
And yeah, I would sacrifice characters if it serves roleplay purposes. My good aligned gnome artificer would not dream of trying to save the evil drow, who wants to kill her friends in the Grove ( she is best buddies with Rolan and siblings, protective of Silfy, who seems not fit into Mols little crime sindicate, and has a crush on Nettie)