Hey @Parallax! Just saw that this was open again
Hopefully this will assuage your fears regarding Brandon's handling of Dalinar's arc and I'll also try to keep it short this time.
Seeing Dalinar's actions as irredeemable is totally a valid opinion. There are plenty of politically charged real-world equivalents that might put a hamper on the idea of forgiveness for a crime of that scale. The main issue I think is Dalinar's payoff in Oathbringer's conclusion seemed to reflect one side of the argument as morally superior. That is part of the narrative itself, I think and given Brandon's handling of similar issues in Mistborn era 1 (Koloss army, Well of Ascension), mainly thematic to this body of work and an open-ended question to the readers.
It's perfectly valid to see the Oathbringer conclusion as the author's stance, Brandon has said that is the side he leans towards but he also understands the other side. I can understand the trepidation though, given many other authors have used their works as a sort of socio-political or religious statement. Orson Scott Card's... betrayal comes to mind. But Brandon has directly admitted to similar issues with his writing such as women and LGBT, so I say, give him a chance. I'm still waiting for the LGBT part myself, specifically the 'G' part. You don't have to agree with Dalinar's conclusion. But it is interesting, isn't it? Just have fun with it, watching the story of the other side of the argument than yours and don't let anyone dictate morality to you, take its measure by yourself.