I grew up with the NIV, so it was just natural. It was also the default option when I went to biblegateway.com to copy the text, so I just rolled with it. I know there are some people who would be scandalized that I didn't use the KJV, but that's their problem, not mine.

I wouldn't argue that the modern BIble "disowns" the OT, but some NT authors were doing their best to sweep it under the rug to make their fledgling religion more palatable to the Greeks and Romans. Early Christianity was just a sect (some might say a heresy) of Judaism, so it wasn't inititally designed to appeal to Gentiles. With that lens, you can even argue that the apostle Paul is a more important figure in Christianity than Jesus - indeed, I've seen this argued a few times.

And you know what? These sorts of topics are a lot more interesting to me now that I don't feel compelled to believe the traditional interpretation of them. I became far more interested in the development of early Christian theology after I became an atheist, probably because while I was still a Christian I was afraid of what I would find out if I challenged my beliefs at all. Not an unfounded fear as it turned out, given the arc of my life.