A nameless genin in Naruto dropped one of the most broken abilities during the Chunin Exams that most characters couldn't have handled.

Minato and Naruto having nine-tails' chakra cloaks left most burning questions and mysteries unanswered that Masashi ...

Sarada needs the Rinnegan if she wants to scale up to the stronger enemies in Boruto. She could obtain this power.

Sasuke could finally regain his Rinnegan in Boruto. This power up could allow him to compete with other characters.