The ducts are on the list to do also!
Personally I dont think the hatch vent needs any other carbon bits to compliment it as its quite subtle looking because of where it is and possibly because we are used to seeing the black OEM one, so the carbon doesnt take away too much from the car. If you didnt know NSX's and was browsing over it, it would looks like the carbon hatch vent was always meant to be there.
Where if you add carbon side vents to just about any NSX apart from the dark colors, it stands out a miles. Which personally I'm not a fan off, but as the side vents are quite heavy, when I get the carbon ones for my car, I'm going to paint them to match the car.