Sorry...faith is always an element of salvation.
Abraham sinned all the time. So his faith wasn't actually as you purport. We tend to think of Abraham as the epitome of faith, but he stumbled like everyone, and was unfaithful at times.
I appreciate your position. I'm simply not convinced of it.
But many positive things are said in scripture about Abraham, aren't there? In fact, God held him in such high esteem he promised to make the patriarch the father of many nations and that many nations would be blessed by his seed (Christ). Is not Abraham not the spiritual father of all believers? How come Adam isn't if he was such a great man of faith?
In fact, I'm surprised that you would cast aspersions upon Abraham since he is spoken of so highly in scripture, being accorded the great honor of being called God's "friend" (Isa 41:8; 2Chron 20:7; Jas 2:23). But where are the positive accolades for Adam?
And I can't be convinced of your position because it sends up too many red flags. Your theory presents too many unprecedented things going on in the post-fall account that make me uncomfortable. If God saved Adam apart from faith, that would be unprecedented. But if you say that God saved Adam due to his faith, then we'd need chapter and verse on that, etc, etc.
And then we do have Job's inspired commentary that Adam hid his transgression, and that would have been very displeasing to God.
Or can we find any text in the bible wherein God "drives" his faithful people out of the land? God has always driven his and/or Israel's enemies out of the land or...out of God's temple as Jesus did with his Father's enemies. The fact that God drove Adam out from the garden AND omitted Eve from his decree speaks volumes -- at least to me. Yes...Eve left the Garden with Adam...but that was her temporal punishment -- not eternal!