Mark,
I wanted to thank you for the detail you have provided during this build. I did some work at Eglin Air Force base in the Florida Panhandle in 1996 +/- and I remember looking over an unpainted Mig-21 that was stored outside at the time. If my memory is accurate, it looked EXACTLY like what you have done. There was some variation in the finish of the various alloy panels, some grainier, some smoother, and I thought the workmanship of the entire fuselage was not very good, parts didn't fit well, seams were not even, panels were bent a little - maybe from clumsy maintenance. These thoughts may not be fair to whoever built that plane, maybe the Chinese? because a lot of the problems I saw could have been because the plane I was looking at had been assembled from other airframes.
In any case, I can't see how your model could in any way be improved to match what I think I've remembered.
Very nice indeed.
John