I went to a couple of your fiestas & pretty much had the same experience. There seemed to be 3 groups, the guys with girls, the guys that knew each other and the guys that sat alone, I would have been in the alone group but I was with a buddy. The only opp to check a girl out was when she went to the bathroom. Looking back that was probably the best place to hang out. It was still nice seeing them.in person and in most cases they looked much much better in person.
One suggestion. Have a girl who speaks english act as a hostess, she can approach us lonely guys and see how were doing, explain how it works (I didnt know u could just grab a beer) and she could ask if we wanted to meet a girl, if so she could bring them over, do an introduction and then take her back if she was with a guy. If shes alone, she could stay and sit with a potential new client.