Plasticjunkie, that Phantom is gorgeous!
Here is my 2 cents. I have been around aircraft my whole adult life. started as a GA pilot, then into the Air Force, and now in the airlines.
Aircraft panel lines rarely show unless there is a reason. Like hydraulic fluid/fuel seepage or taxiing thru mud/grass/dirt. Then it is almost always very localized to a specific area.
What does happen is paint wears unevenly and can fade unevenly on all aircraft.
Military aircraft have many removable panels for maintenance and access. These wear around edges and
can be replaced/repainted. Also battle repairs add variations. All of this leads to the look of the Apache.
Wear and tear on military aircraft is a real issue. For a realistic look paint some panels slightly different shades, vary the surface mattness/gloss, and show wear around the maintenance panels and fasteners.
The A-10 looks like it was taken at an airshow. The wing would try to send the best looking aircraft there. That explains the pristine paint.
Airliners should really never show panel lines. everything just fits together too well, they generally don't have many maintenance panels, and they ussually have heavy gloss paint. Add to that the scale of most airliners make the panel lines invisible. What does happen to airlines is the jetway smudge around the boarding door, grease/hydraulic fluid around the flaps/slats and gear, some oil seepage around the engines and APU area, a small bit of carbon deposits around the engine/APU exhaust and the flaps behind the engine.
With military and commercial aviation the aircraft are mission tools. Looking clean and perfect are secondary to being able to fly the mission.
That's been my observations over 30 years in aviation.