Technically, I'd like to see something in CFD or from a windtunnel. What's this car's aero profile? Changes in lap times? Drivability? Cooling? Just because the car looks fast (and stable) doesn't mean it is.
Styling, the above is akin to taking a bazooka to a knife fight. I prefer an elegant understatement.
It's not so important to me how well the car is seen, but what is witnessed or experienced when driving. At one extreme, I give you the 911. The other, a stock Miata with a near 3ft / 1m tall spoiler.
IMO it looks like something out of a cartoon. Why do this to a very nice car? Mine will remain a Dark Horse. I can only imagine how difficult it would be to sell with it looking like that. Sorry but that's how I feel.
This guy is a talented 3D modeler, but his designs are usually about two or three rungs over the top to me. If he dialed it back about 20% I think he'd have something. But the bigger issue, and something I immediately picked up on, is he made major proportional changes to the car, the beltline seems lower, at least near the front, and the wheel arches are considerably larger. You'd have to essentially rebody the entire car with a kit this extensive. So this body kit would be tens of thousands of dollars, if not more. It wouldn't just be a small spoiler you could buy for a few hundred bucks and bolt on, it's changing everything.
I hope he's able to do something with this. But if he wanted to make something production feasible, he would need to dial it back a tad.