I'm a Christian, been a bit of a debater in my past. But of late I've simply had better things to do than argue the beginnings of the universe. I'll gladly share what I believe if someone is interested but I have homework and such to do.
The rape verse, I'll give a short poke at my own opinion, lacking any research. This is strictly off the top of my head.
At that time an unmarried woman was likely in her early teens, perhaps as young as 12. Seeing as a woman lacking her virginity who HASN'T been widowed was not marriageable, a man who rendered her so would be forced to take responsibility for her well being.
At the time a woman wasn't "property" strictly speaking, she was considered a "charge" of her father followed by her husband. Her father wasn't expected to keep care of her for her entire life. The arranged marriage system(which seriously worked out better than it got credit for, despite being rather crap) was broken in this case and the least disruptive way to handle the problem was to make the rapist take responsibility for the life he'd shattered.
I wouldn't say it makes as much sense in a society like ours, but then again Deuteronomy wasn't aimed at gentiles anyway. This particular bank of commandments, as I recall, was specifically for the Hebrew people for the purpose of setting them apart.
Rather refrain from starting a full blown discussion, starting a heavy schedule this week. Just wanted to address that particular point as I had some inkling as to an answer.