Agreed. If we are even allowed to change anything about them - it should be their attributes, and leave it at that. OR give us more unique items like that circlet which gives 18 int (like after I have gotten it I was sad I didn't give Astarion the arcane trickster subclass, since spell accuracy is tied to int, gonna do that on my 3rd playthrough). In BG1 and BG2 we had access to so many stat changing items, but of course once acquired, we had to make one choice - who should wear it.
I'd say leave the origin companions the way they are. In worst case we can always multiclass them...
