If you are off-road, I recommend keeping it minimalistic and light. Gear has a way of adding up. No need for a shower enclosure, that's just one more thing to setup/clean/take-down/pack away. If there are strangers in the vicinity, you can always wear swim trunks, then you don't have to worry about an enclosure. The truck itself will block views from 180 degrees.
I gutted the inside of my AIrstream of all the crap it comes with. Ditched inside shower and all the particle board cabinets. Weight lost, and room gained was impressive. Heavy particle board gone, and tacked on an outside shower that is just a hose and spray nozzle, and a stainless pole to hold.
Ok but the reality is I need to convince my wife and daughter and they want an enclosure.
They will be grateful if you teach them to live in a little more carefree way in the out-of-doors. If they want to be modest it's just a good excuse to put on one of their swimsuits. The important part for a good out-of-doors shower experience is what you stand on. I don't want it to feel flimsy or cheap. And bare dirt is no good either, for obvious reasons.
