well perhaps taking it off diconnecting when any player comes near you... miners tend to clump, so even if safe chars that aren't yours come by you'll get d/c
what i do with cotobo is set it to d/c on attacking players and blue players... this keeps my miner relatively safe, my miner tends to only get pked by high levels that can one hit him.
hope this helps a bit
EDIT: There's no "safe list" on my copy of COtobo of the kind you are asking about.