Air controls are a thing of the past. I have a couple dozen of them collecting dust at my shop. They work best if the pump pulls hard on the well, because the vacuum has to pull a diaphragm back against a spring. No vacuum to speak of, no air.
I agree with everyone else, a bladder tank is the best thing. And there are good ones and bad ones. With your galvanized tank, you can hook a compressor to the schrader valve and push the water out of the tank. Once air spits out of the faucet, (this is done with the pump motor off) close it and put about 20 lbs of just air pressure in the tank. Now turn the pump back on. You will see an amazing difference in the time it takes to come back on again. This can be done when necessary. The whole reason for this is to prevent the motor from cycling any more than necessary. Cycling a motor wears them out.