If you overlay the Congressional districts I bet you can see the impact of Gerrymandering on some of these maps. When a party can receive well less than 50% of the votes and attain well more than 50% of the house seats you must congratulate them on trampling the intent of representative Democracy.
That would be useful. I think gerrymandering is still sort of abstract and inside baseball to a lot of people, but a stark visualization could make it a hell of a lot more immediate.