Actually, those are a lot of common misconceptions I don't even know who propagated, in reference to the flaws of the Bible. That's why I said that I've been convinced it's the truth, because I've looked into those things. Interestingly enough, the Bible is the most historically accurate document we own. I'm not sure what you mean about the Garden of Eden, maybe you can clarify, but I'll touch on the other issues.
A lot of people have this huge misconception of 'translation errors'. Some people think that it started out in Greek (New Testament, anyway), was then translated to Latin, then to German, and way down the line we get to English and a telephone effect occurs. This is not what happened. We have more manuscripts of the New Testament than any of our other historical documents which we hold true. Take for instance, the life of Julius Caesar, I believe there is something like ten times the amount of manuscripts of the New Testament than the account of Caesar's life. Now, we take all of that as historical fact. And yet four accounts recounting the same events, which are more historically backed up, are not taken to have the same credibility? Sounds fishy if you ask me.
What we have of Biblical manuscripts show that, overall, they are nearly identical to one another. The similarity, in percentages, is about the following. 99.2% for the Old Testament, and 99.7% for the New Testament. Beyond that, even if we only had what was quoted in the writing of the Early Christians, we would basically be able to recreate almost the entire New Testament. At the very bare minimum, we know that nothing was tampered with and if anything changed between translations, a vast majority of them are incredibly negligible. Like, a lot of the time, it's just differences as to whether or not they wrote "Jesus Christ" or "Christ Jesus," honestly something that matters pretty little. And, if you do take the opportunity to read through the Bible, when the footnotes say 'Or whatever', they're not talking about differences in manuscripts, it just means that there's a different way of translating it. And for those instances, they're always footnoted. By the way, a lot of this information I'm getting from a lecture event I attended at Harvard where Dr. Douglas Jacoby was speaking, so you know I'm not just pulling things out of thin air. Look him up, though, he's ridiculously legit and actually has read and does read on occasion the Bible in the original Greek and Hebrew--not to mention has seen (or held) and read some of the most important manuscripts we own.
As for power struggles, that's only been things instituted by churches, and not what's been changed in the actual documents. And even if they did change the actual documents, there would be more than enough evidence to show that something was changed.
I'm not sure what you mean as far as the evangelist being taken out of the Bible. There were way more than four or five evangelists. Every Christian was an evangelist and did what they could to spread God's Word. So I'm not really sure what you mean in that or where you got that information.
As for 'how the world worked back then', I'd have to dismiss that as well. Hebrews 4:12 (NIV) says that "The Word of God is living and active," meaning that it does have application in our daily lives and does still apply. However, if you don't believe me, I'll just tell you this: Since I became a Christian and changed the things in my life I have been a much happier and overall a better person. Regardless of whether or not the teachings seem 'outdated' they simply work. That's just the honest truth of it. If I did not have God I would have committed suicide years ago. Seriously. But He pulled me out of the depths of my life, and most people hardly recognize me these days in comparison. That's not to say I lost any part of myself, but instead I became more myself than I ever was when I was doing 'what I wanted'.
But study it out for yourself if you don't believe me. Douglas Jacoby has tons of books that discuss much of the Bible incredibly intelligently, and he's an amazingly well-educated historian. Beyond that, I'd also recommend a book called 'More Than a Carpenter'. The title is kinda cheesy and sounds like a 'Jesus changed my life story' but it's actually about the proofs behind the Bible, within it and outside of it. It's only like a hundred pages, but after reading that book I've never doubted again in my entire life. From the moment I read that book on I was 100% sure that Jesus was Lord and that what was in the New Testament was what He said. There was no getting around it.
So, that's a short little synopsis of why I believe, and also an answer to some of your questions. I've read, heard, and seen much more than I've put here. This is just the things that immediately applied and that I had room for.