You cracked a rotor? That seems quite unusual. Are they making OEM rotors in China? Just to be completely subjective, I never liked the idea of upgrading the stock brake platform with higher performance pads running on stock rotors.
Anyway, I also have a '13 GT/CS and one of the reasons I bought it is because
the suspension and brakes were completely stock. This is so I could mod both myself. Now, as far as tracking my car? I have not done this so, I don't know how the stock brakes and rotors would hold up. If yours is an example of this, it could
be the result of not also upgrading the rotors.
If I were just to upgrade the brakes on the cheap, brake pads, brake lines and rotors
would be the minimum I'd go with. However, One of the 'mods' I'm planning to do is to put the Brembo
GT500 package on my GT. It comes with 15 inch rotors and probably would do well under track conditions.
The subject of brakes is another one of those things that's completely subjective so, you may get many other ideas on aftermarket brake combinations which are just as good and sometimes, better depending on the size of your wallet. Anyway, that's my take. You'll get a better answer from someone who doe
s track their car as experience is a key to good feedback.