If you are looking for a purely on-road car, I would suggest looking at a Prius V. There are three sizes for the Prius, the C (small hatchback), the normal, and the V: (large hatch / midsize wagon, similar in size to an Outback). Obviously the V has zero off-pavement capability (as in dirt parking lots are a bit much) but if you are sticking to the pavement, it is probably the highest MPG wagon on the market today. 35-45 MPG is what I typically see when I drive it. I am 6'1" and it is comfy to drive but I dont know if it is long enough to sleep in. One owner said he set the drivers seat for his 6'1 frame and there was 6' of cargo room behind him. It sounds like there would be enough sleeping room if you are willing to pull the front seats forward. Also, 2nd row seats lay flat, and I have heard the driver and passenger seats go flat as well. Also, the 2016 model and new can tow 1500 lbs. That doesn't sound like much, but you can fit a lot of camping gear in a small cargo trailer and stay under weight.