Add a new field type that allows you to select someone from a list of users invited to participate in the review.
For example, sometimes we log defects on behalf of someone else (for example, if during an in-person review with a recorder), so we currently work around this limitation by including a text field where you manually type the name of the person who raised the defect.
Also wondering if there would be value in providing the option to select from a list of all collaborator users (not just the ones added to the review).