I obviously don't know what the story is gonna look like at full release, and therefore I don't know if this would work, but I like the following idea: What if you don't die from the tadpole when you rest too much, but it does change you a little bit every time you rest (toward 'evil', whatever that could mean in the context). so if you wanted to keep your sanity, resting as little as possible would be a goal for you.
