I think there are a lot of misconceptions about what a CITES listing would mean, which Matt is doing a good job trying to correct.
CITES listing would probably mean that the price of a ray will be a bit higher. There would be more permitting involved to bring a animal across borders. It might lessen the amount of wild caught cheap stingrays in the aquarium trade. I personally wouldn't be too distressed about this as it is my belief that most of these animals do not live long. Is this elitist? Maybe it is but I can live with that. Different animals have different reproductive strategies. Freshwater rays take a while to reach sexual maturity and they do not produce a lot of young. Animals with this reproductive strategy and more vulnerable than an animal that can reach sexual maturity in several months and produce thousands of offspring in a relatively short period of time. Besides, keeping a ray in a way that has a good chance of the ray doing well is an expensive undertaking. If the price of the ray is more, it will weed out those people who think it will do fine in their 20 gallon tank.
CITES is concerned with trade of plants and animals. This could help protect rays from the commercial fishery which has a potential to grow and have a big impact on their population.
CITES II listing will not mean that people cannot breed rays or that all rays have to be chipped.