There are no patterns of wear, everything is uniform.
Where the handle is, you would see more wear, a haze of grime from a thousand hands touching the surface.
The loop of the handle has a certain amount of play in it, it would probably swing and rattle, rubbing against the door behind it, metal rubbed wood looks different from hand rubbed wood.
The slide for the lock would have parts that are near polished from the motion of sliding over and over again, the places where hands touch it would have a different finish.
Would the carriage bolts, the handle loop, the flat strap that attaches the handle loop and the body of the lock all be made of exactly the same metal, with exactly the same rust?
How is the bottom part of the latch attached to the door frame?
If the metal got that rusty, its safe to assume it probably got wet. if it was getting wet, there would probably be some trace of the rust being washed down over the wood.
Realism isn’t about high res textures or the best HDRI environment, it’s about capturing the feeling of a scene. and a huge part of that feeling is the dynamic interactions that happened before the image is recorded. Weathering is a process that is tied to its context. Considering how these pieces Weather and wear together will open the door to creating a realistic scene.