I came here because I wanted to see how the artists handled this difficult subject. I like the first picture the best. I imagine God would appear ‘in person’ as He did before the destruction of Sodom and Gomorrah in Gen 18. Abraham clearly recognized Him then, so that suggests Abraham had seen a physical likeness of God.
The Father is spirit, Jesus told us, and so does not manifest Himself in that way. But the Son certainly does, repeatedly, including preincarnately; so your supposition has the advantage of feasibility, in addition to being a logical deduction and the best theory covering all the revealed facts. So, I agree. I like that first one too—that’s why it’s first.