The thing is that the 2nd gen is a work of art, unburdened by aerodynamic concerns. The 3rd gen has some visual awkwardness which I believe comes from putting aerodynamics before style. No one is going to look at the 2nd gen's rear window treatment and the 3rd gen's, and call the 3rd gen's a visual improvement. But if you look at how smoothly the roof transitions into the rear deck, it has to be close to perfect aerodynamically-
The 3rd gen also introduced the laid back windshield, the rounded transition from the windshield/a pillars into the roof, windshield wipers hidden under the hood, semi-recessed door handles. The hidden gas cap is pretty sweet, it's just not as cool as the exposed gas cap on the 2nd gen. 3rd gen doesn't have a filler neck going through the trunk though (too bad 73 and 74 had a hump for the vapor recovery tank in the trunk).
Not sure how many 2nd gens had head rests or seat belts, or when safety glass came in.
I've never heard anyone say they built a 3rd gen because it is a better driver's car, but apparently the improvements were appreciated in 71 -
I'm looking forward to seeing what the 3rd gen is like with modern aftermarket suspension, steering, tires and brakes -
I've seen it said a couple times that modern hot hatches are faster than the supercars of the 90's, and improvements in tire technology are the biggest reason why. So how good can a 3rd gen Charger be? Surely it's a step above that 4 door Coronet, with the shorter and wider chassis and the better driving position. The Charger may not crash as well as a modern car (although there's a whole Smart car worth of car between the driver and the front bumper), but the thin A pillars of the Charger are a major win in the visibility department. Thick A pillars suck!
The 3rd gen may be the most unappreciated performance car with a racing pedigree of all time. I don't know Fords and Chevies, but only one car made the greatest NASCAR driver into "The King." And also raced at Le Mans, and continues to be drag raced to this day. I don't know why it isn't more valued. It's only crime is that the 2nd gen Charger is better looking. The 3rd gen isn't bad looking - it's great if set up right. It just isn't as good looking as the car that is generally considered the best looking muscle car.
Look how sexy that thing is!