I think this is one of the most important of all the questions you ask. As far as I know, these stats don't exist yet but stats on the number of deleted posts may exist and you will be updated monthly in the meta.

I don't think I've missed anything about the thread locking statistics that the moderators do, if there is one then I'm sure some users have published it here. But there is nothing wrong if you want to propose it to the admin if in the future statistics like this are needed.