I think that having one explicitly good Illithid leaves open the question as to whether the other Illithid who captured you may have some kind of "good" motive. End justifies the means kind of thing. It could lead to some interesting moral dilemmas.
I really like the nuance that Larian has brought to all the "evilness" stuff in BG3. The introduction of Viconia in BG2 (and the drow in general) was very poorly written.
From my perspective, I rock up to this group of people about to burn her at the stake literally just for being a drow. My only option is to let her be murdered or kill the crowd of bloodthirsty peasants. I rescue her and then immediately she makes it clear that no, she really is a remorseless murderer.
Anyway, I shouldn't dwell on this too much in this thread. I'm just very happy about Larian going all-in on the idea of having characters who have agency as individuals and are able to act counter to their default alignment. (Evil druids, rebellious goblins, good mindflayers, etc.)