Didn't see anyone trading pins at ASA 14U Nationals last summer during opening ceremonies. More of a 12U and below trend. DDs are still in a ziplock bag from her younger days at USFA World Series.
Since you have time my suggestion is to design or go with a nicer pin and a smaller number per girl. Believe me word gets out when you have a nicer pin, and it says a lot about who you are. Our league waited until the last minute and got a generic type pin. We were all disappointed, and a bit embarrassed to say the least. The girls want something cool, and many girls at states did not want to trade with us because our pins were for lack of a better term cheesy. So for nationals we knew we had to do something. So our team moms had towels and water bottles made. We attached the pin to the towel, then rolled it up and put it in a water bottle. Needless to say it saved the day!