I just finished reading that and I agree with what Horner says except for the part about standardized engine parts. He's on the right track when he says that a car's success should be about the driver, chassis and engine. I think far too much energy and money is spent on aerodynamics and I don't blame the teams for that, obviously they just want the cars to go faster and that's an area with the greatest gains. The teams do all have a lot of money invested into their tunnels but if Formula 1 put a long range plan into affect, like single plane front wings by 2020 and tunnel ban by 2025, then tunnel dependency could be wound down and new money would not be invested.
We took a pole on the best looking era of Formula 1 and it was the early 90's cars that won, if I remember correctly. These cars had big tires, slender bodies and single plane wings. If you watch races from back then, cars could follow right on each others gearbox and it was awesome. We could have cars like that again with the right rules changes. Increase mechanical grip, reduce aero grip and add power. I would still like to see some creativity with the engines and believe that having a variety of engine configurations would be great for the show.