Apache6, I really like your all female 2nd Tennessee Cavalry Regiment idea.
I also like your adventure idea- good ol' fashioned horse rustlin' = good times.
As for wagon design, wood is lighter, but the value of wood as a construction material and fuel source would increase after the TDM. A cut-down truck bed would work almost just as well. Depending on the truck, it wouldn't really be that much heavier than sturdy wood construction, once all the unnecessary bits and pieces were removed. More likely would be a hybrid wagon using a cut-down truck chassis with a wooden frame. When I lived in Uruguay back in the early '90s, there were lots of these ad hoc horse or mule-drawn wagons- the drivers would do freelance garbage collection.
On my bike ride today, I passed a father and daughter on horseback. In some parts of the U.S., horse ownership is pretty common. My town of Marana (basically a large, unincorporated suburb of Tucson) just announced the construction of a $13,000,000 rodeo grounds. In my old, more rural neighborhood, half the people on my block owned at least one horse.
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