Winsome, here's how I see it:
The Reformation wasn't really the upheaval that many people assume it to be. Luther, Calvin, etc. each began from the assumption that Catholic doctrine was essentially sound, but each tweaked it in their own way.
Hence, there's valid truths in Catholicism. There's valid truths in Orthodoxy. And each Protestant variant has its own good and valid truths. But you'll rarely find THE truth by going from one extreme to another.
The problem with the Ref was that it didn't really go back to the Bible. They began with a flawed system and altered it in many ways.
Want to find the truth? Forget the old traditions and start with the Bible, without the baggage of the old ways. You might be surprised at what you find.
Of course (LOL), as a Lutheran now, I disagree...
While you are spot on that Luther (and Reformed and Anglican theologians) did not go to ground zero and re-invent everything, nor do we think they should have (That would include deciding - from scratch - what is and is not Scripture, the Trinity, the Two Natures, etc.).
IMHO, Luther DOES "buy" into a lot of the western, Catholic "mind set" - including original sin, a rather judicial soteriology (both a result, in part, of his fasination with St. Augustine and the Book of Romans), and a strongly cognative/theological emphasis. As a former Catholic myself, this - in many ways - made Lutheranism perhaps easier to "get" than Orthodoxy would be. But, I gladly admit, my many conservations with Orthodox friends (rarely online, my Orthodox conservations of merit have all been personal) have impressed me greatly. And moved me with a profound sense of mystery, an emphasis on worship and spirituality rather than dogma, an emphasis on US rather than denominational institutions. In all these things, I feel passionately that Lutherans and Orthodox share some stuff and are closer, but we are children of Catholism - and it shows.
But to the issue: I think western Christianity (until recent embraces of relativism) was probably guilty of "over-thinking" and of just taking ourselves and our theories too seriously. The church is US - not me. The church is about God and our relationshp with him - not factoids. The "vicarious atonement" concept (largely from St. Augustine) largely embraced by Calvinists (and much of Protestantism, historically anyway) makes a lot of sense to me - but I hesitate to call it dogma. Luther often spoke in terms that Lutheran Gustaf Aulen and (then Lutheran) Jaroslav Pelikan called the "Christus Victor" atonement view, and others have been suggested in Christianity. But, from my readings in Lutheran Confessions or my Lutheran Dogmatics books, there is no one theory presented dogmatically. Rather, the teaching is this: Justification is by God's grace in Christ embraced by faith in Christ. Not much more than that is affirmed doctrinally. So, while CURRENTLY I tend to embrace the Vicarious Atonement/Augustian/judicial view as the one that is most helpful to me, I'm not in nay sense dogmatic about that and I've very open to other views. And I wonder if ALL these various theories are a bit moot, a bit over thinking, a bit taking away from the glorious and wonderful Gospel: JESUS is the Savior, salvation is found in the Cross of Christ. WHY that is true is a nice question, but not one I MUST answer - definitively, dogmatically.
To the issue of SIN, I tend to embrace this rather as instructed in my Catholic years by Catholic teachers. That a part of our fallenness is a sin, a brokenness, a twistedness. It's simply a part of our nature; not by virtue of our DNA but of our relationship to Adam. This is just a part of who we are. This is what we mean by "original sin." Now, it CAN have symptoms, which we all "actual sins." Just as when I have a cold. I may have symptoms of such (caughs, sneezes, running nose). I may not - but I probably (at some point) will. Perhaps, with good cold meds, I can make those symptoms disappear but I still have the cold (there's a danger in that I may THINK I don't!). Symptoms may be sins of thought, word or deed. It may be those things done or not done - things I should have said or done or thought - but did not, things I should NOT have said or thought or done - but did. Those Lutherans call SINS (or again, actual or actualized sins). Example: I shoot my neighbor. Is my pulling the trigger and aiming the gun at my neighbor, killing him, is that a sin? I think so. But the heart of the matter is MUCH deeper than that! It started with something twisted in me, something that caused hate and disrepect and a lack of love to overtake me, something that lead to me pulling the trigger. Now, maybe I did NOT shoot my neighbor - but that doesn't mean I'm without sin, it only means that symptom didn't materialize (good thing!). We are sinners, we don't always necessarily sin. Sins flow from our heart, from what's inside of us - not the other way around. That's MY (probably very western) view...
I hope I didn't in any way divert the thread, the opening post is a good one from my perspective, too.