Try to remember your first playthrough...
I do ... and maybe im paranoid, but from the first look at those choices, they seemed shady ... i mean come on, its the only dialogue option Narrator is pointing out, if that isnt suspicious then i dont know what is.
So i was using the tadpole first in my third playthroug.

Also ... now when im thinking about it ...
Im not sure here since it is some time ago ... but wasnt the tag [ILLITHID][WISDOM], or [TADPOLE][WISDOM] or something like that?
And even in conversations with your temmates, the text after the tag usualy litteraly say "use your tadpole powers to ..."

obviously appealing for someone that wants to play "the evil" choice
Exactly ...
And that alone should raise red flag.

Evil powers come for a cost.

The dream appears right after the firsts dialogs temptation and if I'm not wrong, you gain the power after the first one.
Nah ... after second one.

At first Daisy only tells "where are you" and that is whole dream done ...
In second you meet her, and no matter how much you resist her, you get "parting gift".

At this point the story is mostly "the tadpole will become more and more powerfull and you will probably loose control/become a mindflayer".
Im sory, but this sounds like a speculation ...
After all, the only situation where we are told that tadpole has become more powerfull is when Omleuum give us his potion ...
And yes, we know (if we have told the interview with Swen ... OR if we actualy listen to every single one companion we have

) that there possibly may be consequences ... but so far nobody really know what.

Nothing makes the player understand that your character (>< the tadpole) is going to become more and more powerfull if you embrace the tadpole's power.
Its not explicitly said ... true ...
But as far i remember (i dont, had to google

) that sentence is litteraly: "As the symbol glows, power courses through you. Authority."
If this dont tells you that by using this option you are seizing some kind of power ... then what would?

On top of that, even if you use it your quest remains to "find a cure"... So I really don't see any temptation related to the special power.
Well, changing quest would hardly be a temptation after all ... that sounds more like consequence.

And there IS consequence ...
After all, if you are abusing your tadpole powers, your [ILLITHID] tag in text change to [TRUE SOUL].

And so I don't see why good players shouldn't have some kind of powers too for being able to "resist" the tadpole's influence. Exactly like you gain special power in BG1/2 for doing "good" things even if something "evil" runs through your veins
Well ... maybe they could.
I mean i didnt try to say that they "cant" ... just that as far as i know, the curently planned reward for Good characters is different than new power.

But then there should be consequences for both. :-/