That is a great response. It seems the more we learn, the more we are convinced that there are no general rules. Gunsmiths moved around.
Making a gun to emulate or evoke an original attributed to a certain area and time is a fun and worthwhile challenge.
If you are asking, "What features would help evoke a Virginia origin for a Pre-Revolutionary War styled rifle for most re-enactors today?" I'd suggest:
Maple stock (most of the time) that may or may not have as prominent a cheekpiece as Pennsylvania guns of the same attributed period.
Swamped barrel at least .45 caliber and an inch or more in thickness at the breech (same as a Pennsylvania gun).
English styled round faced flintlock lock of good size (more often than in Pennsylvania, though Germanic locks were used in the South and English locks in the North).
Tang carving, if any, that is "scalloped"- best to study originals.
Brass mounts (90% or more of the time), perhaps of less Germanic styling than Pennsylvania guns.
Those are the guidelines I'd use for "Generic Colonial Virginia". But Okwaho, FRS, and TG are great sources. They and others who don't post here have handled many more than I, who am currently mostly a bookworm when it comes to Southern guns.