There would need to be some degree of confidentiality and protection to prevent possible reprisals after a complaint. If there's a pending application by the person making the complaint, their application ought to be set aside and put on a separate track from the immigration consultant who is handling it.
Our members have told me of their fear that immigration consultants have contacts with so many different levels of the immigration process that it would be very easy for them to take a person's application and move it to the bottom of the pile. Even though that might not be the case, they feel that it's real. There needs to be some way to give them security that filing a complaint does not in any way jeopardize the process of their application. It would help if their application were segued off into a different process.