I'm not in scouts, but I do a fair amount of mixed gender hiking and camping. My favorite hiking attire is also my favorite changing attire. That is a kilt. I find hiking and camping in a kilt to be very easy and comfortable. I am have some Scottish heritage so I am very proud of it. Changing clothes in a kilt is as simple as sliding a pair of pants on and removing the kilt. The same in reverse. Fasten the kilt, remove the pants and I'm ready to go.
I am not saying it would be the best alternative for everyone, but it sure is better than messing around in a hammock trying to be a contortionist. And it saves stress on the ropes.