Shawn,
I would say rated so that anyone could get a Scaley, Carrera or Ninco and get it on the track without the need to chance the motor. I’m betting on the wheelbase, track and tire width limitations of those cars to be the equalizer; if that’s not the case we could review the rules, add gear limitations or something of that sort (I really don’t think that we will need something like that).
One thing to remember is that you can use any brand of gears/pinions other than Slot.it, avoiding the problem with their variable pitch gears (10, 11 tooth inline pinions), and getting more RPMs at the wheel without having the car sounding like a Jumbo jet. Scaleuato and BBR (MB Slot) manufacture fixed pitch gear with a separate stop collars — good stuff.