I agree with @patio11, this seems like an amazing service that I can't wait to use now that I have discovered it, but similar to those running open proxies on the net and thus creating negative externalities for the rest of the web, you have a certain responsibility to block abuse before it is reported to the hosting provider.

Maybe something like Sift Science could help automatically create these heuristics. You could just modify your script to notify their systems every time abuse is reported, and it could learn the features of potential abusers.