Just because you're saved doesn't mean it's okay to sin or to avoid doing rightly. The difference is that the Law made the one (i.e. salvation) requisite to the other (i.e. doing rightly). With Paul, however, the fear of death that the Law imposed has been replaced with the law of Love in which there is no fear of death for we are identified in Christ who is righteous and we are therefore righteous in Him and cannot be otherwise.
Notice also that your objections are all based in the flesh. What we do or do not do. Paul addresses this issue directly...
Romans 7: 15 For what I am doing, I do not understand. For what I will to do, that I do not practice; but what I hate, that I do. 16 If, then, I do what I will not to do, I agree with the law that it is good. 17 But now, it is no longer I who do it, but sin that dwells in me. 18 For I know that in me (that is, in my flesh) nothing good dwells; for to will is present with me, but how to perform what is good I do not find. 19 For the good that I will to do, I do not do; but the evil I will not to do, that I practice. 20 Now if I do what I will not to do, it is no longer I who do it, but sin that dwells in me.
21 I find then a law, that evil is present with me, the one who wills to do good. 22 For I delight in the law of God according to the inward man. 23 But I see another law in my members, warring against the law of my mind, and bringing me into captivity to the law of sin which is in my members.
24 O wretched man that I am! Who will deliver me from this body of death? 25 I thank God—through Jesus Christ our Lord!
So then, with the mind I myself serve the law of God, but with the flesh the law of sin.
Paul also directly answers your objection as asked...
1 Corinthians 3:9 For we are God’s fellow workers; you are God’s field, you are God’s building. 10 According to the grace of God which was given to me, as a wise master builder I have laid the foundation, and another builds on it. But let each one take heed how he builds on it. 11 For no other foundation can anyone lay than that which is laid, which is Jesus Christ. 12 Now if anyone builds on this foundation with gold, silver, precious stones, wood, hay, straw, 13 each one’s work will become clear; for the Day will declare it, because it will be revealed by fire; and the fire will test each one’s work, of what sort it is. 14 If anyone’s work which he has built on it endures, he will receive a reward. 15 If anyone’s work is burned, he will suffer loss; but he himself will be saved, yet so as through fire.
Resting in Him,
Clete