Gotta be honest...to me, this Pre-Crisis/Post-Crisis argument is just absurd. I can't take anyone who argues for or against one or the other seriously, because the solution to which one is use is obvious: both. It's just that simple. How can you honor a character's entire history when you're stuck on one particular version?
I could care less if the version Millar prefers is the version that was around for most of the character's history. All that means to me is that HE'S the one stuck in a rut. That version limits the character, by limiting his options and his development. Is that what Millar wants to do? Again, he seems to be more about the concepts involved. And that's all well and good, but so far, Millar's take on Superman is just...obvious. Using Krypton is obvious. Using Braniac is obvious. There's nothing new or interesting to it from what he's said, as far as I can tell. Could there be? Sure, but I have yet to hear a whisper of it.