Is there a way to delete a whole tradition's worth of books and courses?

Josh, like Graham, I would suggest just hiding stuff, rather than trying to get them removed from your account, for a few reasons:

1. Future dynamic pricing of packages: if you own it, you can get credit for it. You never know how FL might mix things up in future library bundles. Don't throw away free money.
2. Research and comparative study: you might want to do that some day, and it's better to have access to primary sources rather than secondhand or further removed reports.
3. Regarding deletion of a tradition or a group as a whole: I certainly wouldn't trust any automated/bulk process or tagging, whether from FL or the community, for handling something like that. You wouldn't want to make any mistakes you may regret later.