If you're not fortunate enough to have a Cayenne equipped with Porsche's factory air suspension, then lowering springs should be on your short list of upgrades.  Along with better handling and significantly less body roll, you get an unbelievable improvement in appearance by eliminating the largely unnecessary gap between the fenders and tires.  All this comes with no compromise to the comfortable ride quality of the Cayenne.

Front Lowering:  1.6 inches
Rear Lowering:  1.6 inches