Part of the challenge is that people want different things. I'd just like to get off this "status quo" of cookie-cutter, virtually identical cars, running at basically the same performance levels for the last 20-25 years. Break open the rulebook and let there be innovation and competing designs. Stop nerfing the cars so they aren't slower than they were 30 years ago. Yes, that increases risk, but if there's no risk I'm not really that interested.
Alternatively, go in the opposite direction--back to "STOCK" cars which are closely based on production cars, so that there's actually some commonality between the cars being raced on the track and what you can go buy in a showroom. Then again, the traditional car market is collapsing and even within the car market there are few race-capable RWD chassis options.
There are many reasons why neither of these directions will happen, but that's what would get me interested in the sport again.