Keep in mind that there are likely to be other companions as well. I think we got the most interesting and developed ones first...*think". I also think we have met two or three of them and they are all "good" whereas the current ones are neutral at best.
I'm confused, because I am pretty sure Wyll is good aligned (despite a few mistakes made), Gale so far seemes more on the good than neutral side, Shadowheart...eh, pretty tame for a priestess of
Shar. Do I still need to spoiler it?

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That's 3 out of 5 available companions who are good to neutral at worst.
The more I think about it the more reason I see behind D&D going away from alignments, considering our companions are also origin characters so I'm sure there will be lots of children-saving Astarions and tiefling-saving Lea'zels soon enough and alignments would only hinder that
