/3/ - 3DCG

>>531643
It will look decent for a phone game. For a simulator or something else, you'll need to go in depth. Panels should be about 1px and not completely opaque, I would do a dark brown color for the fuselage and wings with and completely black for the engine cowling, and set the opacity to about 50%.
Add soot, oil streaks, exhaust stains, paint chipping etc. Remember that these planes were mass produced and not exactly perfect like today's jet fighters. Vibrations caused oil and fuel to leak a little, and the paint wasn't exactly high grade.
Look at Simmer's Paint Shop. Although they've died out a bit, they still have some useful tutorials still on the site.