El Gato... you don't belong here...
Yes there already is a feature that prevents a map from being played repeatedly...
It can be setup to prevent the last map from being played or from letting a map be played until x number of maps have also been played.
Now here's the funny thing. When I was a mere player I really wanted this feature(even asked for it when this forum was elsewhere). Now that I run a little 1v1 dm server I'm likly missing something obvious... but how does one allow maps to be repeated? In a 1v1 situation most guys want to play deck time after time... I'm not going to try and understand that but it happens.
I can also see this mutator turning into a admin mod. Just needs to have the ability for an adminstrator to login and change more settings. Even having an easy way to pick presets would be great too...