You could also make a bed platform with a pull out drawer. Gives a lot more storage that is well organized.
My daughter and SIL have set their Grand Cherokee up with a short platform, removed part of the rear seat, and made curtains for the windows. Very neat little setup which they are enjoying until they an afford a trailer.
I think you are being smart with the payload and watching your weight. It may not be the most luxurious accomodations, but sounds like it is a compromise you are willing to make work.