How can I maximize MPG with 50,000 mile/year delivery service?

Thanks again everyone for your comments! I'm still consistently getting > 60mpg using Toyota's recommended tire pressure and not exceeding 55mph. I can't increase the tire pressure because the roads here are absolutely horrible and the ride is already borderline uncomfortable with all of the potholes and uneven pavement. I'm very happy to set and forget both cruise and auto climate with a/c and still see results over 60mpg it's simply amazing! Hopefully this will not be drastically different in the winter when the temperature drops below freezing constantly which brings me to my next question: how is this car in the winter? Buffalo, NY here so we definitely get massive snowfall and occasional blizzards (we had two or three last year). I don't expect it to drive like a 4x4 but I'm hoping the relatively high ground clearance for a small car combined with the proportional weight distribution from the rear battery pack will be enough to get me through. Does anyone have actual experience with driving this car through over 4" of snow? I'd love to hear all of your input on driving through > a few inches of snow. And Thanks again everyone for your input this is really a great forum I'm glad I stumbled upon it!