Has DJI considered developing an Aerial Relay module.  Perhaps such a thing already exist - maybe from a third party.

What I'm seeking / considering is a way to improve signal strength when your signal is impacted by line of sight and / or other environmental conditions create interference.  Could I put a signal relay module on an Inspire and parked it at say 200 feet above ground level near or directly above me and use it to boost the signal between my controller and a second Inspire which I'm actively piloting?

I have been thinking about this same thing for quite awhile. What part of the world do you live in. I'm in LA. I think this would be a big change to possibilities. You would need a pilot for the second drone but this would work.