Speaking of party size: all four in the party have Illithid powers. Can Gale or Shadowheart still use their Illithid persuasion even if Tav has used up theirs? They should. I haven't tried but I bet they can't.
Conversely, if only Tav "surrenders" to using the Illithid powers, why do the rest of the party get them as well even if they don't use them? Clearly this should work on an individual basis.
It's all a little bit too railroaded. I don't, and no sane person should, like using unknown powers from an alien parasite and letting that presence have more and more hold over you. Especially when you know from the True Souls they are trying to mind control you. The only sane conclusion would be to resist using the powers and try to get rid of the parasite as soon as possible. Unless your Wisdom is 8. It all stinks a little bit of "you will like these awesome cool powers for game purposes and screw role playing".
I for one fully expect to be rewarded for resisting using the tadpoles. That doesn't mean I wouldn't have someone in the party use them.
