"In the beginning, (when) God created the heavens and the earth..."
I think the "In the beginning" preface in the scripture is better evidence of Hebrew belief in ex nihilo creation than the presence or absence of the "when." The preface implies that there was a beginning, which requires a "time" when there was nothing (that's a tough concept, because if there is nothing--no energy, space or matter--then there is no time either). If the proverbial primordial soup pre-existed God or existed alongside God through eternity, and God merely provided order to the chaos like building a sandcastle on a beach, then the point at which order arose from disorder was no "beginning." The primordial soup would require an environment or a space, that space would require time, and pre-existing time forecloses any mention of a beginning. Whether it is "In the beginning, God" or "In the beginning, when God...", it is clear that the Hebrews believed that God pre-existed (or super-existed?--God, as Tillich would point out, doesn't exist like the universe exists) the beginning, and that the universe as we know it did not exist until after the beginning. Logic tells us that if the disordered components of the universe existed before the beginning, then the beginning wouldn't have been a beginning, at least in a temporal sense.
I lack the ability to debate which translation is more accurate, but I don't think either supports the notion that Hebrews believed in platonic creation. Even if we read pre-existing primordial components of the universe into Genesis 1:1, there's no evidence that the Hebrews believed that God was not also the ultimate creator of those components. The NT writers believed creation ex nihilo, and that with the influence of the Greek platonic beliefs on creation. If there were to be a trend, we'd expect it to be toward the Greek philosophers rather than away, particularly given that much of Christian doctrine isn't purely Hebrew but a combination of Greek and Hebrew (thanks to Paul). I don't see anything to warrant the jump from ex nihilo to platonic creation belief, even if the premise regarding the "when" is accepted and the "In the beginning" preface is ignored.
I also don't think the idea that evil is merely the byproduct of primordial disorder is biblical at all. Probably the earliest OT writing, Job, describes an active evil force confronting God. Jesus not only tells us that Satan exists, but he is tempted himself by Satan, not by some morally neutral remnant of primordial disorder. If the primordial disorder theory were to be accepted, we'd have to conclude that Adam, Eve, Jesus, and everyone before and since has not been tempted by a temptor, but by a mythical figment of our collective imaginations. The theory also borders on dualism, where God is a force opposing disorder, yet not a force with sovereinty over disorder. That's an unsettling proposition.
I think the better position is that taken by Paul--a man educated in Greek (platonic) philosophy in the Romans 11 doxology: "For from him and through him and to him are all things. To him be the glory forever."
