I would argue it this way. You say that you are an OEC, but then it seems that you still want to have some 6 24h day creation, though maybe i am confused or wrong there.
At any rate, let’s pose the case of YEC.
Presently, I have no reason to accept any of that proposition of YEC – other than the fact that God created the heavens and the earth (which I think we all agree on). More importantly, I have spent the larger part of my life from age 22 confronting this question. At 22, I was confronted with the issue of science and faith. I had taken on a faith. So I changed my focus from the arts to the sciences and tried to find out about these things. I went through a lot of geology coursework, I went through chemistry, I finished with physics, and now i work in the biotechnology area. What I say of the matter is “I accept evolution”, because we should not just “believe in” things when we do science, The meaning of “accept” is that I could not find anything that was definitely wrong with it. That could be because I am not clever enough to think of an alternative, but it certainly isn’t the case that I haven’t tried. Moreover, if I thought I had a good idea, I would investigate the matter thoroughly – at least God willing. If I understand your OEC, then just as you, I never had a problem with the age of the universe. … and there are a multitude of problems with the 6000 year old universe.
Suppose that I arrive at those pearly gates and Peter is standing there. He says to me, “Wayne, you thought the earth was old, the universe even older, maybe no single Adam and Eve, the flood was not global, and that living things on earth came about by evolution. Well, it turns out YEC is the right answer.” … well, quite frankly, I would be stunned, if that is what it can be called for someone from the grave, but I suppose that there would be a perfectly acceptable explanation (after all, I can only see through the glass dimly).
I would feel that it would be very much the same for your objection – particularly if it is the case that there was no single Adam and Eve and life came about by macro evolution. God would have a perfectly good and acceptable explanation.
The thing that I maybe have problems with on arguing these issues, is that we start to forget about God’s sovereignty. Whereas the contents of the Bible and the message that provides is very important to our faith, spiritual growth and guidance, we should not make the bible an idol. We have fellowship with other believers, we have prayer to help us conform to God’s ways, we have teaching and we have scripture. But finally, it is that relationship with God (not merely following rules) that matters far more. We cannot earn our salvation, though periodically, we find ourselves trying. Yet, God is sovereign and what God did, said, or whatever simply is – whether we like it or not. So it is important to accept whatever is graciously, and not put too many of our special requirement on it. We want to follow Jesus, and follow the way of the light; everything else pales to that.
I am not 100% happy with the no Adam proposition either, but this is the difference between science and faith. We should not constrain science with theology, and we should not constrain theology with science. The solution always seems tortured. If we agree that God created the heavens and the earth, and the Jesus died for our sins, etc. these are the things we should put our hopes on, and our models are simply toys to be played with and put back in the box when the journey across the Jordan comes time.
by Grace we proceed,