It would be nice to see when a map was last played so we know when it will be available for nomination again. If possible, just a number to the right of the map in the actual nomination list counting down every map until it can be nominated again. That would be awesome. For example,
sm_maphistory shows a list of maps in console and how they were voted for. Not what you are looking for but a way of seeing how long ago a map was played.