I agree with you for the most part.
As Lugez said, 1 year before getting engaged is a bit early. I've been with my husband for 3 1/2 years, living together for 2 1/2 years, and married for 1 1/2 years. Honestly, I feel like we're just getting to the point where we should have been considering marriage. We've gotten to know eachother pretty thoroughly , we've matured individually and as a couple and have finally reached a point in our lives where we feel settled and as though we can grow together.
I wouldn't have said this without the experience I have now, but I really do believe an extensive amount of time spent growing and maturing outside of a school setting "in the real world" is necessary. Not for everyone I realize... some people are just that compatible, but with divorce rate so high I would really take the risk of wasting years of my life with someone who wasn't going to work out in the end.
I also think its very important to live together. Its only fair to both individuals to know exactly what they're getting themselves in to. I think if the couple really loved eachother they would try to make things work. Sometimes it doesn't so why force it? If you decide you can't live together its better than getting married first and having to go through a big divorce.
Sex before marriage... yeah sexual chemistry is a big deal. Going feeling unsatisfied can be rough. You have to keep in mind also, some people lose their sex drive over time and while sex may be satisfying now, it might not always be that way. Its just something you'll have to remember, and be prepared to take care of your own needs when that happens
I can understand how the whole parent approval things would be important to most, but honestly it wouldnt stop me from marrying who i wanted to be with.