How about if a manufacturer made keyboard wrist wrest with a trackpad in the centre, I'm sure people like imav would love it. course with a logitech marble would be even better and the ability to improve the tilt/stability of the keyboard would be a good bonus too. Just thinking aloud anyway, I used to be good at track balls, but at the moment the mouse is my pointing device of choice and i am useless at ball pointers now though.
Another way of pointing i've imagined is, imagine a pointing device that would move based on tilting the keyboard when u pressed a button, this would not take the space of a trackball or trackpad but still require the usual right, click left click even a scroll and of course the move mouse button. But the drawbacks is the moveable keyboard that might need to be reset once you wanna type, might even be heavy and/or larger depending on tilt mechanism