I realize that asking people to read such a lengthy project is a tall order, so I will try to sum up some of my thought here in the hopes that it may be a little easier to respond to. Honestly, this is a difficult thing to do because the project (see link above) was my attempt to distill the research that would easily fill a few books into something approachable by everyday people.
Having said that, my basic premises is that much of the instruction we see in the Bible regarding sexual behaviour is heavily culturally conditioned. I think if we would dig into it a little more, we would conclude that there are a lot of other factors impacting why those sets of behaviours were commanded of Scriptures original audiences rather than some universal set of sexual ethics. I believe there are clear principles, but that they do not dictate what we have been taught they do. Examining these principles and the cultural context that informed them, and then attempting to reapply them to a 21st century context, would (I believe) lead us to a different understanding of what Biblical standards for things like premarital sex, adultery, and lust should be.
Failure to do this causes some significant problems. One, because traditional standards prevent any meaningful discussion of other things connected to sexuality, we fail to speak into (or even think about) some important areas that the Bible does want to address. Two, we impose a burden on 21st century Christians that I don't believe they were meant to bear. This not only causes undue Kingdom energy to go into bearing this burden, but I think makes the Scriptures seem irrelevant to the outside world in this area. Three, what is traditionally espoused regarding Biblical sexual standards is out of sync with many examples from Scripture itself, thus causing confusion and misunderstanding among Christians and unnecessary ridicule from non-Christians.
What I attempt to do in my project is go back and reexamine words like porneia (sexual immorality) and moicheia (adultery) to try to unearth more of the cultural context. I think it is only through understanding better what breadth of meaning these words had to the original NT writers, that we can correctly interpret the passages which warn against them in the NT.
If I have caught anyone's attention and you would like to know more, let me know (private messages are fine too) and I will try to post condensed version of my various analyses.