You can use options in text, you know? You don't have to set the variables to the options...
Also, there is no need to do smth like this system, you can just revoke 'bukkit.plugins' and 'bukkit.pl' perms from 'default', or just 'on command "/plugins":', 'cancel event' and 'send "Plugins (0):'

¯\_(ツ)_/¯

And command blocker: why not revoke perms???