I suppose this is really about enhancing a virtual reality.
Disney are particularly good at this, some of the illusions they create in some of the 3D theatre presentations (compressed air blasts round the ankles coinciding with images of mice coming out of the screen, a seat cushion deflating to simulate acceleration of a seat, coupled with appropriate images are just two examples that come to mind. A trip to DisneParis, or if you can manage it, a chat with some of their engineers and designers might be worthwhile.
A chat with some flighgt simulator or other training simulator companies might be a good idea. at first sight it seems that the solution is to use all the sensess (including, smell, taste?) to complement each other.
Of course, for wargaming, having real and loaded weapons pointing at the gamer, linked to the opponent's computer would generate a very realistic scenario, but I doubt it would be very popular