I downloaded MCForge once, and it had a cmd called /xundo. It erased everything they ever did, so if they were a griefer, then all you had to do was kick them, then use it on them. I think it is a really good cmd, because some people forget to /undo before they kick, and /xundo would erase it. They also had a /undo all cmd, which erased everything you did, and would be a really good command for when you are online, and people think you griefed...To make things short, I just want the command, and I think it would just keep you busy.
..I still think you need longer tempban..