I think you are confused, the difference between D & L is not the throttle map, it is the CVT ratio map that is changed.
ie. "L" holds the CVT ratio to a "lower" ratio, the reason you get more regen is because the input side of the CVT is spinning the electric motor faster. (Electric motor is on the input side, final drive is on the output side.)
Sport mode is what we believe remaps the throttle map to a different, perhaps more logarithmic curve.