The Airstream concept is a great idea. You may want to check out all the forums and see what issues folks are having. Airstream is known for weak frames. They use the shell as part of the structure. Their 22' model from the early 2000s are having major frame issues and it isn't isolated to just a few of them. They seem to be cracking right behind the rear axle mount. Avion and Silver Streak among other similar designs used heavier frames but they are no longer in business. I think Airstream added a lot of weight over the years without making the frames stronger.
When the Airsteam floor starts to deteriorate from water damage, it allows the shell to seperate from the frame. This causes significant damage and the best way to fix it is to do an entire shell of restoration. You won't see many shell off restorations of the other similar makes because they have a stronger frame and the floor is installed differently where the restoration can take place with the shell still on the frame.