"With this understanding, looking at Genesis 1-3, it becomes rather apparant to me that God alone is the observer and that He is relating "Day" from the Creation perspective to "day" from a creature perspective, i.e. on earth."
It explains why the moon and sun seem to have been made on the 4th day with the stars just beginning to appear as well...even though you have the beginnings of plant life on the third day. The photons from other suns would just be reaching our solars system at about that time taking into account the time dilation effects that you describe...millions of years passing by in a flash...depending ones perspective.
Moses of course though he could not see God's face("no man could and live"), who being hidden and protected in the cleft of the rock(a wonderful hymn by the way), had the perspective of seeing God's "hinder parts", in a sense was able to see "where God had been"...Moses wrote his 5 books including Genesis based on his conversations with God and of the revelatory nature of being in God's "TIMELESS" presence...so he was able to "see" in a sense what God saw as God ordered creation into being! This "seeing" of course was only in the limited human sense. Moses was only a man after all so he could only write what he saw ...God's spirit would have to translate what Moses saw into the spiritual knowledge that resides in every believer's heart!
Mine is somewhat different in that I read Genesis 1 through 3 as applying to both heaven and earth and thus describing acts of creation in both. For instance, Gen 2:5 - that plants were created (in heaven) before they were put in the earth.
Here's a link if you are interested in more of my view on Origins and Scriptures