John..., my two cents is that design, relative to wire work is extremely important. This is especially true with European work. With Kentucky rifles I don't feel it's as critical, but it's still important.
Most wire work on Kentucky rifles was relatively simple. Also, I wouldn't say wire work on Kentucky rifles was nessisarily rare, but it wasn't common. Boarders around lock and side plate panels, boarders around cheek inlays, accents to carving, etc., is where most wire is found on Kentuckies.
The vast majority of wire work on Kentucky rifles is characterized by a single wire in the wood. Scrolls, volutes, etc., were "blended" into the main "stem" to create a design. With European work, most of the work was done by "stacking" multiple wires into the same opening, and using the various ends to create the volutes, scrolls, etc. Because of this, wire found on American pieces is typically a little thicker than what was used on European pieces.
Personally, I draw everything on paper first, then transfer the design to the stock. Once it's on the stock, I'll typically tweak some things as needed, but never "free hand" anything without first drawing it on the stock.... I spend a lot of time in design, and struggle with it mightily.
Ed