Never been on Route 66. Helped cousin Eddie drive a 40 ft monico diesel pusher to Florida about an hour ahead of a bad winter storm. Ice hanging off the mirrors, strong cross wind, snow build up on edge of road, from mirror to mirror 9 ft 10 inches.
With generator running, boiler going to stay warm, motor home got almost 10 mpg.
I told cousin Eddie, next time he needs someone to help get to Florida, lose my number.
That was enough to find out I don't want to drive a semi like motor home.
I think you could have more fun and spend less driving a comfortable car or van. However camping would have an advantage, no bed bugs. Bed bugs is becoming a major problem in the US.
I was told, there isn't an EPA approved chemical to kill them.
I've never taken a trail ride across the US. I think I would check into that first.