Are the ends of your pine logs up off the ground, or are they laying in contact with the soil?
Hard to say without seeing what you have now. I don't know what the odds are of you getting another 8 years out of the existing pine logs, especially if they are already showing signs of rot.
If it were me, and I were going to the trouble of re-decking it, I'd put something more rot-resistant in than the peeled pine. Then if my deck died 8 years from now, I might be more comfortable re-using whatever rot-resistant wood I had used in this repair effort. Otherwise, you may be faced with tearing of your decking a few years down the road, replacing the beams, and deciding whether to put new decking on, or re-use the decking that has now lost half it's life...