It's actually not as simple as you think. The amount of adverse yaw you encounter will depend on the flying speed. The worst condition for adverse yaw is near the stall point where the down traveling aileron moves that wing to a high lift coefficient and a high induced drag as a result. But if you're ripping along at a high cruise speed where the wing is operating at a very low lift coefficient then you will see extremely little or no adverse yawing. In fact at high speeds with a strongly cambered airfoil such as found on most Cubs it's quite possible that the up traveling aileron may force that side to such a low lift coefficient or even to a negative Cl that it produces a PROverse yaw. See? It's not quite as clear as you may think.

Anyhow since it's a Cub I'm assuming you spend more time putting around closer to the stall than you do trying to emulate a pylon racer. As such a 2:1 up to down would not be a bad thing at all. But even with that if you're trying to do a low and slow turn out at the end of the runway it's a wise choice to use only small control inputs. After all, even with some differential in the system if you're near the stall the half travel on the down side could be the straw that breaks the camel's back and you end up with a tip stall. When flying slow it's a wise pilot that moderates the aileron use and decides to use just a little and be more patient with the model's roll rate.