I just measured my dining room table and a runner about 44" X 18" is perfect for the center of the table. It is set up now for seating 6 and they have plenty of "elbow" room. I still have room to leave the runner in place and when I set the table I can use placemats. Maybe that might answer some questions.
To become a judge, not really sure Ube. I have entered several quilts, 2-4 each year for a while now. I have won Grand Champion twice, 1 st place several times, 3-4 2nd place and 1 year even a 3rd place ribbon. Never quite understood that one
but you can never judge your own. Each county fair will usually have 2-3 judges, then they collaborate to determine a Grand Champion. The county called me and asked if I would come in for an interview. I went and through a series of questions they asked if I would be a judge. When you judge 1 county, I think word of mouth travels and then another county may call you if they need a judge. Each county and State Fair has a list of requirements that you have to go by when you judge and they ask that you follow those to the best of your ability. Not sure I answered your question, that is just what happened in my case.