I agree with all of these. However, I think the primary thing that God's image means in Gn 1.26-28 is that humanity was created to have dominion [1.26, 1.28]. Go read it. It's clear. And dominion is not for mere citizens or peasants. Dominion is for royalty. We were made, in some sense, to be "kings." This says something about our Creator and not necessarily our innate worth.
All of this is not mere conjecture or attempted exegetical insight. It's clearly what God's image means. Here's why:
If we read the end of the book, to what are we restored? In what way are we "co-heirs" with Christ [Rom 8.17]? Revelation 19-22 says that we will be raised to reign with Him, world without end. That is our lot in Christ - the full restoration of God's image and all that that entails. This is also why our Lord, who flawlessly bore the Father's image on earth, preached that "the kingdom is here" [Mt 4.17, Mk 1.15].
God's plan to fix the marred image could not have been accomplished by any other means except by the full image-bearer [Col 1.15, 1.19], the Second Adam [Rom 5.12-21].