Great! My feeling is that it would be good if the OPs can self-patrol as that helps mods.

So, it would be an OR function: if admin OR OP hides a comment, then it is hidden.

I think it will be very useful to have the ability to make such "non-reward" judgments.

Yes, it could lead to some using it for censorship, but then any commenter who feels strongly about that can open a new post - at that point, the OP of the original thread has no editorial control, only the admin has that with respect to the new post.

As everything is merely hidden rather than deleted, readers can always check what is being hidden - this in itself will lead to the admin having a reputation for good "cleaning up" or as a censor.

Thanks