Since all 1/10 car is about in the same weight, try to match the damping hardness with your friends car. Soft damping tends to give smooth cornering action while harder one will make your car acting more direct to the steering input. Personally I prefer soft damping as it also give better tires millage (highly noticable on EP rubber) and the car feels kind of very light when cornering.

You gain more steering with higher front roll center, try using 1mm shims under the front upper arms instead of the 2mm standard.