If we are to have a WRC car, all we need is to start with the RB4, increases maximum suspension travel to 250mm (aka what WRC cars actually have), enable the use of dual rate progressive springs (main and helper spring setups), enable use of 4 way or frequency selective dampers, increase power to 300hp, increase torque to around 60 kg, enable a selection of tires to cope with anything a WRC car would be expected to cope with, proper bump stops, stronger, more damage resistant suspension, a roll cage and racing seats/harnesses, at least 1 passenger per car (to simulate co driver) and finally an antilag system (aka bang-bang whenever the throttle is lifted).