You do not believe that God sets you free so that you can become His servant. You beieve that God has preordained each and every move of yours, each and every thought, that you are jjst a tool in God's hands whether you do good or evil.
Not only are we depraved; we are depraved by God's design! Yet, the Scripture tells us differently. It tells us that man was God's crown-jewel, created in His image and likeness, free and capable of making decisions.
Would you not agree that God wants man to be with HBim in Paradise? Well, he was! Are you now suggesting that God intentionally corrupted His own crown-jewel? If man is nothing but a slave to God, then none of what transpired in Paradise was man's own doing, but only God's. God must have choregraphed the Fall in the Garden of Eden and is ultimately responsible for the evil that followed.
The use of the word "slave" in English translations of Romans is quite unfortunate because it can be used to imply something which isn't there. The word in question is douloV which really means a bondsman or a type of bound house servant not a field or quarry slave. The KJV translates it as "bondsman" and that's pretty close. In the first instance Harley cited we are servants in the house of the Evil One, in the second, in the House of the Lord.