Since Wyll and Shadowheart were revised, Astarion’s writing is the only one I have a problem with.
IMO, it’s pretty dumb that Astarion always puts a knife to your throat, no matter how many companions you have with you. Unless you are role playing a pacifist, there is really no good reason not to arrack him (in self defense) during either the initial encounter or when he tries to bite you. I don’t mind the writing for Astarion after that, but it’s not surprising that people who are more concerned with role-playing just kill him during one of those two early events.