That depends.
Its not a good a rule of thumb. It needs to be like Goldilock's porridge... just right. Yes if its too hard to apply the force, then more throw can help. But definately don't want too much. That's disconcerting!
Most race drivers prefer to control by modulating force rather than distance the foot travels. For example see Carroll Smith, Tune to Win, 1978, pages 111-12.
My own experience has been that this applies to street and autocross as well. I prefer to modulate using the heel and ankle rather than moving the leg from the knee. Heel rests on the floor.
Obviously if the required force can not be easily applied, the smaller piston may be needed. Sometimes all it needs is a change of pad compounds to ones with more bite. This usually comes with increases in pad wear, but its worth it.
It is much easier to modulate, for example, 300 psi of brake pressure over 2" of travel than 1/2". Too little travel gives you the on/off effect. Too much can wear you out, but I find more is better than less.
