We use teh rudder to keep the ball in the middle (unless we are intending a slip/skid. Like cornering a car, it is really smooth to anticipate the need for application of control and apply that control in a measure appropriate to maintian control as desired. When you corner a car, you don't wait for it to drift across the centerline before steering, you steer a bit to anticipate the turn and then adjust accordingly.
Today while flying home in my mighty Cessna 150, I was playing at this. If I roll left and right 10 degrees either side of wings level, without touching the pedals, the ball will be 3/4 of a ball diameter out by the first cycle, and more than a whole ball out by the second cycle. If I roll from level to 30 degrees bank with no pedal, the ball will be 1 1/2 ball diameters out before I reach the 30 degree bank angle.
For this reason, as mentioned before, I lead my turns in all cases with pedal. It is noteworthy that my 150 is STOL kitted, so the ailerons are more effective, and the effective dihedral very slightly less. It's a "M" model, so it has the larges rudder of all 150's and is thesame as a 152 in this regard.
My observations of the day... Pilot DAR