While weight further back from the tractor provides more fulcrum effect with the counter balance process, never overlook the traction benefits from adding weight at the tires (2 sources-wheel weights and loading tires).
With loaded tires the extra weight is on the ground, the tractor frame only carries extra weight when a wheel leaves the ground. Makes tractor less likely to roll-over. I add the ballast box when I might max out the fel (grapple, tree puller, heavy loose material).
