Unique situation: What tow vehicle checks all the boxes?

Think about it, increasing from 7 to 9 MPG is a 28% increase. That's HUGE.

It takes energy to move weight. Some of it is wasted but not as much as you think.

The trailer backing assist system is for people who haven't already developed skills to back trailers. Your learning curve is due to old habits that are counter to the new system.