When the game fully launches, those that have gotten into the habit of full resting anytime they want are gonna find themselves turning into Ilithid, game over.
I don't think so:
The other True Souls don't show any inclination of their metamorphosis completing either, so the Tadpoles are probably modified in a way as to not do that, like they conclude in-game (or at least modified to have the morph be postponed indefinitely). I do think however that using the Tadpole powers too much is going to leave you more susceptible to the will of the Big Bads in the act 1 finale and perhaps lead to alternative content there.
Also those strange events are dependant on you using the Tadpole powers (and full resting). If you never use the Tadpole you can full rest however much you want without any such ill effects.
