I was idly sketching a bit, and came to the realization that a profile that has the shape of an symerical extended hexagon seems awfully pretty to me.
This is the first design I came up with, I call it the "blimp" its a large canned ham sort of thing.
Then I came up with the "submarine" which has a more conventional 4' height, but has a pop up to give you standing height.
I'm not a designer like Andrew or Mike. These are obviously "back of the napkin" designs. But I notice a couple of things:
thing one: the hexagon shape Extends the lenth of the body past the edge of the trailer. On the submarine, a raised sleeping platform( shown in the sketch, but not labelled) could be parked in the corner of the hexagon, giving you about four feet square to stand and dress or shower. (using a Hartline portashower).
Thing two: Obviously, it has weekenderish ease of construction. Also the shape has a kind of zepplinesque steampunk look about it. I'd like to build a cardboard model to see how it looks in 3D.