If were ever to attempt such a thing (I did once drive from New York City to Dallas), I wouldn't want to simply cover the least amount of miles. I would want to hit particular places of interests, such as certain state or national parks, various historic landmarks, etc, along the way.
Could be helped by making a list of satisfying “I’ve been there” sites in every state, scattered across enough that you don’t have to go far into a state to reach one, yet come out with a smug sense of having “been there”.
This is sounding like it would make for an interesting app to write.