I like your idea about changing the concours for a different purpose, but I am not sure that an adventure bike is the right fit. Most "adventure" bike really cannot bring you on much of an adventure already. Many are too big, too heavy, and too complicated to handle this task. For a true adventure you would want something that is light enough to pick up by yourself, easy to work on in the middle of nowhere with minimal tools, and cheap enough that you can walk away if you destroy it.
The concours would be a bear to pick up by yourself, especially if you were in mud or dirt. I would go with a UJM route that could make a unique commuter bike. Good luck with your plans.