[Grant-53]

The cross section of the body and the ground clearance go a long way in determining side lift and drag. The fairing I built for a city bike is essentially two cones, two feet from the ground. It is barely affected by cross wind. Generating down force instead of lift is key to stability along with reducing drag.
The dustbin fairing Kraig is using generates lift. The cross section is close to being a circle. A tail section helps turn the body into the wind. The Morelli/Aptera body has an horizontal oval shape for lower side drag. The shape looks to be a symmetric air foil with the center line bent in a shallow S curve.
The stability versus response balance is often a rider's preference. A low nose and a higher tail box seems to be a good balance to reduce lift and drag. Angled strakes at the nose can generate down force at the price of more drag.