Is it possible to add a freeform text field to the role assignment section of a review?

I would like to request that a freeform text field be added to the role assignment portion of the review screen that allows you to document the specific role assignment that each person has on the review.  This is different than the moderator, reviewer, author, etc. It is in relation to the role this person has representing a particular effort.  In our case, we have specific work products that require specific program involvement from specific roles like a SW lead, or a Project Engineer, or a Program Manager.  When I identify someone in a review as a reviewer, I want to be able to identify them as the program manager, Project Engineer, etc. We don't want to have a separate template for every work product we review, we want to keep that generic enough to use the same template, but we want to be able to identify who each person is.  We could create a custom field, but we want this to be tied to each review participant directly.  A custom filed would not have that tie. 

I want to be able to show that all of the required reviewers were participants.  Unless I tie them to the actual participants that have time recorded, I can't prove that they were involved.  See below for an example.

Review Role                                  Program Role

  Author                                            System Engineer

  Moderator                                      Lead Systems Engineer

  Reviewer                                        Quality Assurance

  Reviewer                                        Program Manager

  Reviewer                                        Test Engineer

I need to be able to show that the relevant stakeholders participated in the review.  A custom field does not tie a program role with the time spent in the review, but if the review role could have a place to identify the program role, it could be on the same line in the review summary screen.