Truthfully, I think people misunderstand the whole "dangerous quirk" concept. It's not just about creating flashy superpowers; it's about building narrative tension into the character's DNA from the start. When you start with a power that could harm the user or others, you're forced to think about control, ethics, and consequences immediately. That's way more interesting than a character who just gets stronger.
Take something like a quirk that lets someone absorb memories through touch, but it's involuntary and permanent for the victim. Suddenly, you've got a character terrified of physical contact, struggling with guilt over stolen experiences, and maybe even being hunted by people who want to use them as a living recorder. The "danger" isn't just a combat limitation; it defines their entire social existence.
I've tried using generators for my own writing, and the best ones push you toward contradictions. A power that creates life but drains the user's lifespan. Teleportation that leaves a toxic residue at both departure and arrival points. Those aren't just cool abilities; they're instant story engines. They make the character's journey about mastering themselves, not just mastering a technique.