You use as much as you need. I use very little, if no exponential. But that cannot be true, since the output wheel on the servo it self has reverse exponential induced.
And I like it that way. Better to have response then measure it with more than waiting for something to happen. If you have a little tremor, its nice to have some cushion there.
It sounds like you need a more positive response, so i would suggest using less expo. I know that when i fly my freinds jet it feels very sluggish. And when others fly mine they seem alarmed at my settings. So it really comes down to what you get used to become imprinted with, or adjust to your liking. Have fun.
John