Time for Caster/Camber plates that allow more caster. The increase in caster helps center the wheels. With increased caster, turning the wheel side to side causes it to lift the front end of the car. Lifting the front requires extra energy input from the steering wheel, so it isn't always the best plan if you have a manual steering rack.
Edit:
Prior to purchasing C/C plates, have another shop check the wheel balance.
Steering slack needs the efforts of two people to check it out throughly. Place the car on jackstands located under the front A arms as close to the ball joint as possible. This loads the suspension in a similar manner as driving on the road. Lock the steering by turning the ignition key off. Have your helper try to move the tire & wheel assembly right to left while you watch the outer tie rod ends for slack. Watch the steering rack rods to see if the move when trying to turn the wheel. Next relocate yourself to where you can see the rag joint and have your helper move the tire & wheel assembly right to left while you watch.
To check the ball joints, use a long pry bar under the wheel to lift it while watching the A arm for looseness. This time watch for slack in the ball joints.