I have been involved with this event in some way for a number of years. My first Nats was in 1966. I have judged appearance at the Nats more than a few times, including this last Nats. Appearance of a stunt model depends on a number of factors, all of which are difficult at best to quantify. However, I think most will agree that it is easy to see the workmanship that goes into producing a model that looks "nice", however you want to define "nice". Also, it is easy to see if the model has a good finish. Some color schemes may be more attractive than others (to some at least), some color schemes may be more complicated than others, but a good finish is nonetheless a good finish.
The purpose of this post is really to discuss two of the old categories used in appearance judging: originality and realism.
On originality:
Just because a different shaped rudder or wing tips on any of the hundreds of stunt designs that have appeared over the 70+ years of competition, it does not really constitute a "real" original design.
When someone first showed up with a B-17, that deserves some originality points, though when the first appeared, it still was a conventionally configured aircraft with a wing and a trailing stabilizer. Same with a B-25 (been done), an almost scale Wildcat (been done), an F7F Tigercat (been done), and the countless other "near scale" or "semi-scale" models that have appeared over the years. The first person who appears at a contest with a twin pusher canard with a conventional stabilizer would be eligible for full "originality" points. The second person to appear with that configuration would not because his was not "original". A person with a triplane would not get originality points - it has been done before.
Some new definition of what "originality" really means for our precision aerobatic models would need to be developed before originality could be reinstated as a criterion for appearance points in our event of Precision Aerobatics. I do not have the slightest idea on what that definition could be.
On Realism:
Does a "semi-scale" model of a jet fighter with a propeller on the front represent "realism". Some might not think so. Cockpit detail may look nice and might help with the overall impression on the "appearance" of the model, but does it really help with how "real" the airplane looks? Up close maybe, but from a few feet away, so what if there is a complete "realistic" cockpit in the thing? Panel lines? Done well, panel lines might contribute to the "realistic" look of a model. Poorly done panel lines do not help with the appearance of a model - if anything, they detract from the overall appearance of "realism". If panel lines were intended to be a part of the overall appearance to garner "realism" points, that is up to the eyes of the beholder. Panel lines might not be a positive factor.
Regarding painted on canopies as part of "realism" for appearance points. I can remember one Nationals (around 1999) where I judged appearance with Charlie Reeves and Arlie Prezler. After we had things sorted out with the top models in the front rows, we realized that four of the top five models in the front two rows had painted on canopies. So, what does that say for the need for cockpit detail? If cockpit detail is the preference of the builder (which is my preference), then so be it. But a rule should not be such that cockpit detail to any level is needed for the overall appearance of a stunt model. Same with semi-scale designs. If that is the preference of the builder, then again, so be it. A rule should not be in effect that dictates that a model must be a semi-scale or near-scale replica of a full scale airplane to garner full appearance points. If someone wants to build a semi-scale airplane, or at least something that could be called a semi-scale airplane, then fine. Others should not be required to do so to get so called "realism" points. If you want a semi-scale contest, set up a contest to do it. We do not have to change our Precision Aerobatics rules to do so.
If someone wants to add some criteria for what garners appearance points, then do so. The current rule for appearance points covers workmanship and finish without specifically mentioning them. To add "Realism" and/or "Originality" into appearance scoring creates problems that do not need to be introduced into this event.
Just my own unbiased opinions.
Keith