My worry was that normal joysticks don't twist, so not even two of them would do much good. (The additional worry was that aircraft-like motion, easily covered by just a single stick where the throttle could be a thumbwheel or whatever, doesn't work for shuttlecraft. But that's a somewhat different issue.)
OTOH, if a twisting function is to be built in, why not go the full mile and make the movements intuitive? That is, twisting for turns only (pushing forward or left on the pivot counts as twisting, too), and sliding for translations (it's easy to yank a stick laterally fwd/aft or left/right, but a ball is better for up/down yanking). And that could be done with two controllers, or then with just one. Which is why I love the TNG balls, because they look like they could do it all with one hand.
I'm not sure what joy-sticks you've had, but even some of the simplest sticks nowadays have a yaw facility, even things like force-feedback are farely common too.
I don't really understand how a ball that can only control three axis, is any better than a joystick that can only control three axis...? Am I missing how a ball can control direction and thrust at the same time?
If it's that thrust is controlled through the console then surely that brings this all down to preference of control between ball and stick?
IMO, the ball doesn't really give you any feel for where you're at, if there's any visual
representation on the ball of where you're at then you're going to have to take your eyes off whatever you're trying to manauver around, almost the complete removal of tactile feedback doesn't seem like a wise choice especially if it's sensitive work. (That's why I have a problem with touch screen, but that's another thread!)
I used to have a roller-ball mouse when I younger, the one when the ball was on top of it, and I tell you it was a pain in the bum! All you got was cramp in your thumb from trying to move it too quickly. I got rid of it after a year and I've never gone back.
Also, with a stick you can hang on to it if your chair goes out from under you, you can see what it's doing from a distance, when it points up it's off, and you can hold on when the gravity fails!