Both the patent and the trademark sides of the USPTO have committees that advise the Director. The PPAC reviews patent operations, and the TPAC reviews trademark operations. They represent the interests of small entities and individual inventors, and the meetings are open to the public except when addressing confidential information (such as personnel matters). Each meets at least twice a year, and notice of these meetings is posted on their respective webpages, where transcripts of the public meetings are also posted. Comments or questions from the public are accepted before, during, and after meetings.
So if you've got something to say to the USPTO about the policies, goals, performance, budget, and user fees of either patent or trademark operations, this is one way to have your voice heard.