When compared to the standard rotor I would probably turn the drag brake down from wherever you had it before.
Most guys are running drag brake settings 1 (off), 2, or 3... it really depends on the driver's preference or the track conditions.
Also, some guys have been playing around with the minimum drive as well. Most people use setting 1 for the smoothest possible response but if you feel like you need a little bit more snap off the bottom try settings 2 or 3.
Most of the guys ran their GTBs with pretty much the default settings which are now 1% minimum drive and their preference of drag brake which is anywhere from 6-9%.
Some of the guys run negative expo in throttle...anywhere up to 20%... on the brake side some guys run up to 30% negative expo.
Toso ran a Novak 4.5 turn with a 13.0 mm rotor
Ciccarello ran a Novak 4.5 with a 12.3 mm rotor.
Barry was running a Checkpoint (Feigao) brushless motor and I don't really have too many details on the motor itself... they are very secretive over there