The answer, of course, is to make it bigger! According to many, such as the author(s) of How To Build A Teardrop Trailer available on Wikibooks, it is easy to convert an 8-foot trailer into a 10-foot trailer. Since this is not going to be a folding trailer as envisioned by the manufacturers of the trailer frame, the two side-by-side cross members for hinging together the trailer can instead be turned 90° and used to elongate and brace the outer frame members. Still confused? Have a look at the picture.
So now I have a 10′ trailer in the plans, giving me two 2′ sections to put stuff – one for the galley (fridge, stove, sink, microwave, etc.) and one for storage (water tanks, propane water heater [which now does not have to be any particular height], the portable toilet that everyone loves to put next to their food, and a bit of storage accessed inside the berth).