I think the elongated delta which is present on the side of the NX-01 would look better than a "standard" ring around that planet, plus it gives it a more "star fleet" feel. It's a great concept though!
Oh it's definitely canon. Ah. I only now realize that indeed, it wad not present on the NX's side until the refit. My bad!
I like the muted colors and the textures on the background and the metal. Your shadows don't match up though - they are bottom right on the metal, but top left inside the circle. I am guessing this was intentional though?