Thanks for re-starting this, David There is so much to learn from studying this.
First of all, Adam was unique, both in his creation and in his fall (Romans 5:12-1). He was also the apex of all God's creation. All creation was 'good' but after the creation of man, God pronounced it 'very good.' Man is creation's crowning glory. So it was necessary that Adam be created sinless, but, of course, he was also defectable, otherwise the warning of Genesis 2:17 would not have been necessary. 'Truly, this only have I found: that God made man upright, but they have sought out many schemes' (Ecclesiastes 7:29).
May I suggest that before the Fall, Adam was designated prophet, priest and king under God? The 'king' bit is easy: God gave Adam 'dominion over.......all the earth' (Genesis 1:26). Adam is told 'Be fruitful and multiply; fill the earth and subdue it.' This is an instruction that Adam would have had to pass on to his progeny; hence, he was a prophet, speaking the words that God gave him. Eden was a place where God walked; his presence, pre-Fall, was with the first couple. Where else is God's presence with man made manifest? In the Tabernacle (Exodus 40:34), the Temple (1 Kings 8:10-11), in the Church (Matthew 18:20), and in the New Jerusalem (Revelation 21:3). So Eden was a garden temple, a place where man met with God. Therefore Adam was a priest.
So was Adam spiritually alive? Beyond doubt.