Dude, we must have been separated at birth. I have that exact trackball on my desk. It's upside down (trying to unlearn muscle memory of going to track ball vs using nipple) but for some extended "mousing" it's the bees knees.
The GUI tools provided only allow a small amount of adjustment for sensitivity and acceleration. To make large adjustments requires writing to something in a non-obvious part of /sys. It's not really tricky, but it's not very discoverable.
