The concerns raised in #10011 - #10133 should all be addressed now, though there are still >200 URLs that point to the non-book docs, and about half of those are packages.
A lot of those won't be able to be addressed until after work is done on the book to incorporate info from the other docs, so this can probably be closed out once the pages which are currently possible are done. No need to make issues to create pages that do not yet exist, that's all part of a much larger project that doesn't need individual issues.
The book and former wiki content have now been merged into a single set of documentation. I'm going to reuse this issue for tracking associated updates to the help.php content since it's essentially the same task as before, but for the new doc URLs.