The power and weight system was always a broken way of setting up races, the only way that works is in one make races of the exact type of car. Seriously in real racing it's power, weight, aero and other dynamics which is why in racing you ever notice F1, Nascar, Super GT, DTM, V8 supercars they all tend to have regulations on cars to keep them as closely balanced as possible. None of that plain hp/weight limit nonsense you are talking about. PD needs to go over that power limiter thing since so many people have complaints about it but fact is they just need to pay attention a little more closely and they would notice that cars tend to still stay pretty much close to their performance advantages they had when they were stock. NSX, Lotus Elise and LFA still turn out to be seriously hard cars to defeat in the game when driven stock, so of course they will stay that way even with the power limiter. Thing is some cars tend to get a bit better, so they are closer to those cars so you have more cars to go up against them with.
I want someone to show me which cars have overwhelming advantages that the power limiter caused, that wasn't there before the limiter was added. Bet you can't actually find any, in fact the limiter just added more cars to use in a given PP class. PD aren't dumb, they set it up using torque, peak power if anyone cared to look. I tend to play this game a lot, and I have yet to find anything really different power limiter or not.
Now PD should add the option to disable using the power limiter in races, also add a more realistic restrictor plate approach. Which should be able to reduce power and torque dynamically. This would just mean that you would have higher peak power that way, would it not? You'd still have people complaining left right and center, because restrictor plates will still leave you needing ECU mapping and proper gear ratio settings. I hope PD adds ECU mapping to help people take advantage of their cars' power curve.