What about brake torquing?
I thin one reason they use a long shifter is it is seen as "sporty" to have a floor shifter. In the early days of autos it was three-on-the-tree (column shifter, auto) or four-on-the-floor (manual transmission). Putting the auto shifter in the floor console was thus seen as the sporty option. Even late-model Crown Vics had a sport package which moved the shifter to the console from it's normal place on the column.
Automakers have not had luck with smaller systems...Mopar tried pushbutton shifters in the late 50's but people were lunching their trannys by accidentally hitting reverse while moving forward.
The Corvair had a small, t-shaped in-dash shifter, much like a modern Sienna minivan (the newest models). I can't find an image, though.
The biggest, strangest automatic shifter arrangement I can think of was Oldsmobile's Lightning Rods on the 80's 442's.

To upshift, you push the rods forward sequentially from right to left.