[P-hack]

My toyota prius has a throttle with two potentiometers (for redundancy). It would be a fairly simple thing to splice in a microcontroller and two digital potentiometers to create any throttle position to signal map you like, probably something exponential where there is finer control at lower throttle and more rapid change towards full throttle (perhaps with limits to prevent any enrichment modes).

Weigh any such changes against the litigious nature of your locale, as well as actual dangers involved, which I will not go into here because they are largely counterproductive in the innovation space.

But in the case of the prius, it could tie into some feedback for the various efficiency operating modes, such as keeping it in EV mode or coasting mode (or opening it up more when the engine lights to reduce pumping losses). Certainly just having it coast when off the gas could be useful instead of regen.