That was part of my original plan when I was thinking about buying a trailer. Of course then I bought a trailer that has the door on the back!
I think that is a great idea for most the trailers out there. Plus you could use the same rack for the trailer or the car once you get to camp.
There is also a model I've seen that mounts in the receiver, but will swing out allowing someone to open a tailgate, or door, in the case of a trailer. It would probably have a little less drag as the bike will be in the shadow of the trailer rather than up and into the airstream. It would work for me as I'm frameless.
Need to work out a better hook-up. This bent the vent on the top with the straps.
You should be able to take out all of the fore/aft and vertical load on the tear sidewalls, and actually the side-to-side load will come out on the corners of the tear if the 'arms' stay tight to the trailer. You've inspired me!