We don't need any of this. Two words...
Spec.
Class.
That's it. Run everything that came in it. Pick a spec tire, stipulate that you can swap the tx and rx, and that's it. Period.
It would work. "Experts" won't want to run it (and won't be allowed anyway), beginners will have a ball, nobody will be priced out of it, and it provides a great avenue to the more involved classes for the people who get hooked on racing and want to step up (which, by the way, is the whole point).
This exact conversation is 30 years old...before ESC's it was batteries, and before that it motors, and before that it was that all winners were just cheating, etc. The answer does not lie in regulating speed controllers, or the price of the parts.
What is needed is a beginner's class that actually caters to actual beginners. Spec racing is the best way to do that.