Guys I think, you're making this more complicated that it needs to be. Just look at the times of the top drivers in CS, usually their skill levels are about the same, which means, tuning and car platform makes the difference between their times. Usually when these guys drive the same car their times are within a tenth. The logic being these guys are pulling out the max potential from these platforms.
Top ND CS guy Daniel McCelvey East course best time 62.469
Top FRS CS guy David Ogburn East course best time 63.077
On the East course that was supposed to favor speed the ND was 0.6 sec faster.
Top BS guy, Joe Barbato on the East course best time 63.004. The ND was faster. What's wrong with this picture?
The West course which was mostly sweepers that favors lighter cars. In the wet, which would have reduced margins, the ND was 0.4 secs faster. I think this is the data point that should be used when trying to make your argument as it removes a lot of the noise due to driver skill (averages).
I don't like this whole let's build a class for popular cars that the SCCA is favoring. IMHO, it should be based on performance potential ranges.
AS- x to y potential range.
BS- y to z potential range.
etc.
When you start getting lower classes that are faster than higher classes, there is an issue with the way things are being done, IMHO.