If you'd like to debate, and I very much welcome debate, I'd encourage posting a new thread in St. Justin Martyr's corner where you can freely debate with Orthodox Christians without violating forum policies / rules.
Ok but you see how I might get that idea from the wording of the text itself.
"six days you shall labor... for in six days the Lord made the heavens and the earth the seas and all that is in them and rested on the seventh day therefore the Lord blessed the Sabbath day and made it holy"
So it is not like that idea just came out of thin air on my part.
Yes. Certainly - the literal reading of a text is (in a broad sense) a legitimate one; it is precisely this which gave the Pharisees reason to complain against Christ and which, in the 2nd century, gave Trypho the Jew reasons to complain against the Christian (non-literal) understanding of the Old Testament (as recorded in St. Justin Martyr's "Dialogue with Trypho").
You are absolutely right that the Christo-centric understanding of the OT is NOT obvious, NOT self-evident; that is why NO ONE understood who the Messiah was to be prior to the Messiah Himself manifesting. Even at the Cross, the Apostles abandoned Christ (at least in the Synoptic Gospels); they didn't understand the empty tomb.
But we can see in the Gospels (which are the Apostles' later reflections on and interpretations of their experience of Christ) and the other parts of the New Testament that they DID come to understand; and this reflective process of exegeting Christ through the words of the Old Testament continued in the subsequent centuries. I've lots of examples if you want them.
So yes - you are pointing to a text, and I understand the concept / argument you are making. My point, though, is that you are not allowing your interpretation to be Christ-centered enough. That leaves you out of step with the methodology that we see illustrated in the pages of the New Testament and other early christian writings.
BTW - given that Christ was not crucified every 7 days, and given that you are not keeping Sunday in response to the 7th day Sabbath of the Ten commandments - what is the other "7 day" reason that you use?
Here I'm not sure I understand you. We keep Sunday as the day of Christ's Resurrection, the Lord's Day, as recorded in the Book of Acts, the Didache, Pliny's Letter to Trajan, etc. (in other words, as was done from the beginning by the Church). The day before the Resurrection Christ rested in the tomb - He rested on the Sabbath (Saturday). We therefore keep Saturday as the Sabbath. We worship God every day of every week, but those two days are part of the weekly cycle every week (Sabbath and Resurrection).
We do not need to imagine Christ as re-crucified; in the worship of the Church, we encounter the eschaton itself - the timelessness of the eternity of the kingdom is made present by the Holy Spirit in the Person of Jesus Christ in our worship. This timelessness means that we encounter again, or make manifest again, or re-member (to member / put together again), Christ's death and resurrection in our worship; this is just as St. Paul says in his Corinthian correspondence, that as often as we do these things we proclaim Christ's death till He comes.
Is your question "why do we have a seven day week?" Biblical numeric symbolism seems to be an adequate reason. Seven shows up all over the place, and was clearly a significant number for the Biblical authors.
If you like, feel free to copy and past what I've written here up to St. Justin Martyr's corner. If you prefer not to, that's fine. But it is against forum rules to continue debating here.
In Christ,
Macarius
And talk of anything with atoms or chemistry, or anything that requires high math, I'm toast. 
