Surround projectors, head mounted displays, directional sound and cockpit motion are rapidly converging into consumer technologies. Maybe we can immerse the users so well that they fly conservatively because they forget that they're not in real danger.
Aircraft wake is invisible, can last five minutes, descends slowly or spreads across the ground, is blown around by the wind and is extremely dangerous to following aircraft. A future extension to fgd could keep track of the hundreds of miles of wake trails in a given area and notify individual aircraft when they are encountering invisible severe turbulence.
Replication and scalability is only starting to take hold in the desktop environment. A room of several hundred computers acting as X terminals for word processing can reboot and, within a couple of minutes, all be running FlightGear identically. They're ready for the next class of student email@example.com