The basic concept offered to work off of is cars that defy gravity and can fly slowly in close formation, or even come to a full stop while in the air. Seeing as how airplanes don't function that way, some of the problems they run into are not gonna figure in.
Exactly the "concept" I was going for. That these are the "classic flying car" idea, simply to see what the advantages of them would be in an ideal situation. As said in the OP the car is nor more affected by wind and weather than a car on the ground, a high gust of wind causes the car to shudder some but not much else. In some cases a really high gust of wind and a distracted/poor driver may cause a car to blow into a "median"/'shoulder" and crash. But overall these incidences are no more greater than they are now.
The thought experiment was in a "all things being perfect" type thing to avoid
discussions like cars being blown around in the wind. Which also goes to what gturner
above says. Naturally a real flying car, barring any radical change or discoveries in science, are going to have a LOT of problems to overcome. That's not what we're discussing here.
We're discussing what the advantages
of a flying car would be and to do that we're going to assume that the way the flying cars work and are operated causes no higher incidences of accidents, fatalities, and such as ordinary roaded cars. The cars are also just as maneuverable in three dimensions as cars are in two. They can stop in place, after a "breaking distance" due to inertia and hover in one spot.
Essentially the "Back to the Future" version of the flying car. (Ignoring how disturbed by the wind the DeLorean was in 1955) only it's altitude is limited to a few dozen feet off the ground rather than hundreds. Either due to technological limitations or law. It doesn't matter. People aren't flying them at 1,000 feet and crashing them into buildings anymore than people drive their cars across fields and crash into buildings. Maybe it does happen, maybe it doesn't. It's not enough to overcome the "advantages" the cars offer.
It's just a matter of what
the advantages of a flying car are. Or if we'd simply still have the same problems. Would traffic jams really be lessened? Would they be more fuel efficient due to not having to overcome friction with the ground? Would less ground space need to be dedicated to streets and parking structures? (Since you could theoretically have a tall standing parking garage, or even an underground one, without the need for ramps to get between levels.) -For this we'll say the car can "descend" as low as possible to get to the ground. A minor "break" in the altitude limit, you could th erotically fly safely across the Grand Canyon, or descend into it, and ascend out
of it since there's "ground" at the top of the canyon.