It's true there's only a few set positive outcomes in general, but there's an argument to be made why even the less good ones are really good for the characters. I think most of them can fit really well. Won't talk about all of them since there's not much more to say on some.
Wyll:
Wyll made a deal with a devil. It was NEVER going to end well for him I think. You can ofcourse try to get him out of his contract AND save his father but it only delays the inevitable. That being said, I don't think he'll become powerless. Quite a loss surely but I see it more as a 'restart' with a new class. Similar to how everyone got knocked down to level 1 because of the tadpole. So he's not entirely screwed, but I see your point.
Lae'zel:
Yes Vlaakith has wish, but that is an incredibly risky spell, no matter how you slice it. And if she wanted to kill Orpheus or Lae'zel with wish then I think it would have happened. So Lae'zel getting the chance to live her own life, or fight to end Vlaakith's rule is still a great ending for her.
Astarion and Shadowheart:
Putting these two together because I feel they both get shafted in endings but in different ways. Shadowheart could potentially be a Selunite with or without her parents/with or without her scar. And that's good, it deals with loss and pain in different ways. But unless you're a romance partner you don't really get to... see that? Same for Astarion. I don't think anybody walked into Act 2 and beyond with the idea that you'll cure Astarion of his vampirism. Infact, I don't think he'd want to get rid of, as he seems to revel a bit in the power it provides. But if he doesn't become ascended he runs off into the shadows and again, that's all we see if we're not a romance partner for him. I think they're both good for these characters, it just sucks that unless you're romantically involved you have no idea what their plans are, which is what I mean by shafted. Hell, Shadowheart might get to say a few lines at the end by random chance and... that's all. Meanwhile we have Gale who no matter what, because of the orb and the crown, you get a final chat with him for where he's off to next. And then Karlach is just he opposite. No matter who we are to her we get to see her die or go to Avernus, so it's an inverse horrible feeling Gale situation (coupled with the fact that we try 0 things and run out of ideas to fix her).
