I see it the other way around. It is using tadpoles that need to have more consequences. You have the positive ones (powers), but there are barely negative consequences to balance it out.
This would be a perfectly acceptable way to handle this too. And indeed it may be the better way to do it.
If you have options A and B to choose from, you can set up the game to have:
1) A has its rewards, but B also has its (different but equivalent) rewards,
or,
2) A has rewards but also costs, whereas B has neither rewards nor costs,
or,
3) A has both rewards and costs, and B also has (equivalent) rewards and costs.
Here, 3 is what is best game design, but 1 or 2 are also acceptable. But what BG3 has for us is:
4) A has only rewards and no costs, whereas B has no rewards but some costs (namely opportunity costs, i.e. the hidden costs of *not* using the tadpole powers),
where this is absolutely the worst way to design a game.
