We don't cede any powers really because Brexit is showing us we always had the power to leave if we didn't like anything. Any kind of deal is a trade off. If you were a business producing a product that your biggest customers wanted you to follow certain processes or policies, you'd do it if...
We cede sovereign powers to many treaties we have signed up to. NATO, even WTO rules commit you to rules and arbitration that are a trade off on your own sovereignty.