I don't know much about your defences, but a good way of making your site less attractive to phishers might be to put an artificial delay inbetween when a form is submitted and when the owner can get access to the submitted data.
If that delay is longer than it usually takes for an abuse report to come in, and for it to be acted on, then it would prevent phishers from getting any data before the page is taken down. Maybe just do this for free users?