Yup, I also have posted many times in other threads here about being punished for choosing to not use the tadpole powers. As a good-inclined PC, I would NEVER opt to use the tadpole powers, and as a result significant chunks of the game are closed off to me with no offsetting compensation. It is ridiculously bad game design.
There is nothing rewarding about the dream lover sequences, they are short and creepy (which is kind of the point). The powers might feel rewarding, but considering the limited information you can obtain in the game, this seems to be a "give into temptation now, regret it later" situation. In which case it would only bad game design if the devs never implement the negative consequences of tadpole usage.
Yes I agree it could end up being the case that our reward for not using the tadpole powers appears later in the game, in the form of NOT suffering some horrible outcome from having used the powers. That would be AWESOME comeuppance for those who stupidly used the powers.
But for right now, it is very one-sided. And there can be no moral "gray area" here. If one is good-aligned, using the powers of mindflayers who are the epitome of evil would be rather ridiculous.