The father of my son has not had any physical or verbal contact with either of us in over 3 years. He stopped sending voluntary child support a year ago. My son is 7. I have petitioned him for sole custody but he wants only 20 hours of visitation in order to have a permanent visitation schedule. There is not bond between my son & his dad. What should I consider as the next step?

Going to court to have the child support enforced. Let him take you to court for custody
And the Judge will write an visitation order. It will be pretty much up to the Judge to determine how much and when he can have visitations.