Good feedback is specific, brief based, and limited to what matters:
Instead of "the opening feels off": "The product is not visible in the first 3 seconds. Please feature it earlier."
Instead of a list of ten small things: the one or two changes that matter
Instead of new requirements: reference the brief directly. If it was not in the brief, it is not a valid revision request
Always use the Request Changes button inside the platform. It keeps feedback tied to the submission and gives the creator a clear record of what to change.