Now is the time for a new Audi model: the TS 4/5/6. The Touring Sedan would be the modern GT, truly optimised for touring as opposed to more aggressive handling performance: maximum efficiency and comfort at sustained 130kph (80mph). I know, 80mph is not legal in the US, but it is the prevalent speed on most rural interstates and 130kph is the speed limit in most European countries with the exception of Germany.

Its basic kit: TDI, DSG, Quattro. It's suspension and tires would be optimised for quiet, rolling resistance, and wet/dry touring at 130kph. It's engine/gearing optimised for efficiency with full load (lighting, climate, audio) at a sustained 130kph.

Perhaps it should be called the BT (BlueTec Touring), or GT (Green Touring). I think it could easily outsell the S and RS model variants of the 4/5/6 Audi series.