Let me see if I have this straight. You are saying if we had free will we would keep His commandments, so we have Adam’s nature so we don’t have free will? Are you seriously saying THAT?
Yes. Perhaps we should start with a definition of "free will". Isn't it to voluntarily to make decisions? If we have "free will" then one has to ask why don't we keep God's commandments? Moses told us they're not that hard to keep.
Our nature prior to God is bent to do evil. Once we come to a saving knowledge of God, we no longer practice sin. We become slaves to righteousness. But to think that we "freely" make an educational choice to sin or to live a godly life is not logical. Actually-it's rubbish. God expects us to act as His Son and He has given us His law, His Holy Spirit, His Word. And He has bend our will to want to be obedient to Him to the praise of His glory.
We have no excuse when we sin except to acknowledge our shameful behavior knowing that God understands our condition. We choose to sin because of the lust that still remains in our hearts. We don't freely make choices to sin except to be led away by our passions.
Now if you have a better definition of "free will" I'd love to hear it. But it is never used in scripture. There is God's will and there is man's will.