Hi chap, sad times but understandable for a one car house hold. I bought it to facilitate a new baby so the three of us were fine with it from a size perspective. Understand what you mean by the MPG. I know it was going to be low so not a massive issue for me. Luckily my wife now drives and we have a daily driver so ill be selling mine next year to replace it with sports car with 4 seats :)
Depending on your budget id go for a Porsche cayenne. Did heaps of research on them and loved them BUT the petrol high power models still eat fuel.
In terms of selling yours and values, I guess it depends how quickly you want to shift it. I would just look at what is on sale now and then price yours dependent on how quickly you want to shift it.
Stu