Logitech makes great products but sometimes they royally mess up the firmware behind them. I bought their marble trackball three months ago. One of the best trackballs I ever had but they botched the scroll wheel emulation. So it cannot properly zoom in/out around the region of interest in most CAD and I have to keep the mouse connected in parallel. I wrote to them and they don't seem to understand how important this is (for their sales).
This is probably the kind of keyboard we need some day as we get older:
I believe there would be a real market for a keyboard that has a built-in trackball of "Logitech marble class" instead of the numeric pad, but one where the scroll function actually works. A problem would be that there'd need to be a 2nd version for left-hand users. I can do CAD pointing with either hand but most people seem not to.