Analogue joystick input needs throw adjustments

HDC2450 Analog joystick input really needs a left right and reverse \"throw\" or rate setting. As it is I cannot see how if using this as a wheelchair controller for eg I can do this.

I may need say 25 percent reverse output at max stick input.
Or similar with left/right.

Its possible with the RC inputs but not with analog. Which seems odd. Thanks.

John Williamson.