OK, supposing we look at the two elements of ATC discussed here seperatly: seperation and traffic managment.
How about using technology in the aircraft to guarantee seperation (at least to the degree that humans now do so) with some sort of next generation TCAS. This airborn seperation software is backed up by a ground-based, automated seperation service, much like that proposed by NewModel. Then, we needen't be too alarmed if an airborne system or two is on the fritz...the ground-based system will back it up. Likewise, if the ground based system is out, the airborne one is still keeping 'em apart.
Next, develop the ability to select optimum routes provided by an automated collaberation between advanced FMS equipment in the aircraft and advanced URET automation on the ground. The plane picks its own optimum route, taking into account all factors including weather, economics and time to destination, then "runs it by" the URET. If not approved by URET due to whatever reason - traffic, airport congestion at eta, whatever - the plane's equipment looks for the next best route, and so on and so on.
If either airborne or ground-based equipment fails, be it route selection or seperation, the system is not that adversly affected.
How's that sound ?
