No thanks. I cannot imagine what a "roadster" of equivalent safety to the current state of the art would look like. As for the supposed cost reduction - a large scale change like that will always result in higher costs all else being the same.
If you want "better" racing (tongue firmly in cheek) first you have to get rid of the crappy cookie cutter ovals. There were no 1.5 mile nascrap ovals (draft/crash repeat) on the CART schedule circa 1995/6/7 but there were many chassis/engine/tire combos available and many different winners. We had probably four wholesale different aero packages then too (at least with the Reynards or Lolas of the day). Lots of "good" racing back then.
Since then things have gone "spec" in a big way and that hasn't fixed a single thing. In fact, it has probably made things worse at least from the "show" point of view. Full course yellows every single freakin' time and closing the pits doesn't help make anything safer, more "fair" or more exciting either, just dumbs it down ever more.
Hell, look at Indy Lights during the Tasman heyday. These were spec cars, no option anything, no push to pass sillyness, and we won 19 out of 24 races over two seasons between four drivers including two drivers championships and two ROTY. We stripped them down, built them the best we could, the drivers and their engineers worked hard to set them up for the race, and we usually won (or 1-2) by big margins.
In the end, after 15 years in the business and around 30 years of interest, I still say that the rules need to be freed up instead of tightened. One last thing, isn't it a bit of a joke to still have the Louis Scwitser Award when there has been no substantial innovation at the 500 for almost a decade?!?
Edit: this is a topic that almost requires sitting face to face with an abundance of beverages and an equal amount time. I simply cannot type through this subject.
