> If so, were you able to successfully communicate with and/or reasonably work through whatever issue got you black-holed?
Yes. Practically all black-lists have a de-list form that one can use, and most seem to auto-delist fairly fast as soon they don't get any more reports from honey-trap and other sources.
We do have a few custom written ways to detect hacked accounts, and we don't allow users to set their own passwords. We also tend to discourage/deny users who do newsletters and other "higher risk" form of email. All emails sent by websites is sent through different servers, which also mean that a hacked website does not impact the reputation of the email servers.
Events with black lists maybe occur once a year and as I mentioned above, fixed fairly fast. One good tip is to keep an automated eye on the mail queue and react quickly when things start to look wrong.