I don't know if you have had the opportunity yet, but I would suggest that you read the book by Fred Zaspel and Tom Wells, New Covenant Theology. I think it provides an excellent summary of the NCT position (which is admittedly still an evolving one).
As I have interacted with those who advocate NCT, I have discovered some interesting things.
-They are exacting in making assertions on the basis of Scripture alone. Some have characterized NCT as being a "middle ground" between Dispensationalism and Covenant Theology, but if that is true, it is because of good exegesis and not because of a peacemaking attitude.
-They are extremely good at dealing with some of the areas of Covenant Theology that raise problematic questions, such as infant baptism, which OT laws to obey and which to ignore, and why Christ needed to come if people in the OT were saved in the same way they are in the NT.
Thanks for your note and thoughtful comments on the review.
In fact, I have read the NCT book (I read it before I read Barcellos) but I have not written a review yet. I also have a Pastor friend who for a season was very interested in the "New Covenant" approach and attended their annual Bunyan Conference. His interest in the movement has since cooled.
I do not doubt the sincerity of these brothers but I still find Barcellos' critique convincing. The biggest danger I see with NCT is its potential for neglecting the OT's place in the canon (Neo-Marcionite).