Ian,
That's a great paint scheme you chose.
As for the propeller blades the front of the blades would not show that much paint eroded off of them, the leading edges of propellers blades of aircraft operated in the desert would often show paint worn away but the rest of the propeller front usually held up pretty well, the tips of the blades could sometimes show some metal but not very much.
Like in the picture you posted of the 109 you are modeling the back of the propeller blades can (and usually did) have a massive amount of paint missing from the back of them.
What I would do is simply spray more RLM 70 on the front of the propeller blades on your model leaving the tips as they are.
When I weather the back of propeller blades on my models I paint the blades RLM 70 and later will spray on some metall on the back of the prop blades keeping it mostly near the tips. When I spray on the metall I don't thin it very much to make sure the paint spatters a little bit to better represent paint that had been eroded away.
Matrixone