Lucifer and Michael's destinies were preordained, which means they could have come after Destiny... But then Death said that Lucifer and Michael were God's "FIRST big ideas", so I dunno..? I can't imagine Destiny not being considered a "big idea", lol.As for the birthing order/power correlation: Death did seem to allude to it being a 'thing' where Lucifer and Michael are concerned. She stated that because they were God's first big ideas, they came out "undiluted". I can't imagine that being a reference to anything but power/role. /shrug
I just went back and reread Overture. I had forgotten about a few factoids that change the birthing order a bit.
Per Gaiman's most recent info, it would seem that Time and Night were the first concepts in existence. Their eventual 'union' birthed the Endless, along with the rest of creation:
http://i.imgur.com/hU2feOZ.jpg
Hence why Time refers to all of the Endless(even Destiny) and "his children". He is their Father:
http://i.imgur.com/esna7HW.jpg
*Furthermore, Time states that HE gave Destiny "everything he had" as his birthright. He gave Destiny his Book. In essence, Time fashioned the very concept of Destiny -- that's why Time and Destiny are so closely intertwined as concepts.
And as mentioned above: Night is the Mother of the Endless:
http://i.imgur.com/DO8VGKb.jpg
Just so everyone is aware: Night is the embodiment of void/nothingness -- the darkness that existed before creation was spawned:
http://i.imgur.com/wmDIySP.jpg
*Her and Time's roles were better-defined in the first scan.
That being said, this is the revised birthing order of the first few conceptual beings:
1.) Night: she existed before the beginning.
2.) Time: he existed at the beginning, and created Destiny.
3.) Destiny: as mentioned above, he was created by Time directly.
-The rest: they were created by the union of Time and Night, and their stories are all housed within Destiny's Book.
*I believe Lucifer and Michael could fit into the "#1.5" slot, as they existed before the beginning as well... That's kind of open to interpretation, though. /shrug
On a similar, but somewhat unrelated note: Overture was a total mindf*ck. 😖
It also introduced other conceptual beings, like "Dusk"(servant of Night):
http://i.imgur.com/TzHQGCu.jpg
And "Glory":
http://i.imgur.com/ZTtlFp8.jpg
*I am not at all sure what this abstract version of Colonel Sanders' role/purpose is.