Well, I did the ending where

she becomes a mindflayer to save the world/etc.

I was surprised at how (relatively) well that turned out. She seems happy. Everyone sings her praises. There are no ominous hints about her future. And, in my game at least, there is

a friendly neighborhood mindflayer - Omeluum - who could no doubt help her adapt to living as an illithid. Especially the problem of what she's going to eat.

Is this... a happy ending? Hmmm.