I guess I am confused. If the child spends 2 weeks with you and 2 weeks with the Father, then you have what is called shared physical custody. Now you say that after the divorce is final, the Father is moving out of state? If there is distance involved, then shared physical custody is not an option.
What I suggest to you...File for physical custody of the child with your husband having visitation. Make an arrangement that is suitable for an out of state relationship with the child and Father. Ask for the Father to pay (or at least half) of all transportation costs incurred by the transportation with visitation. If your husband is not to do certain things around his first child, I would ask for it to be in your decree as well. Because there is obviously a reason that the first custody decree has it stipulated. Your right about changing orders...Once they are signed and agreed upon, you cannot change them easily without a major change in circumstance. Also, get child support settled as well. If your attorney has not offered you any of this advice, I suggest finding a different attorney.
Good luck!