there are several maps for Jiankou section available here and elsewhere (i.e. tour guides), but most of them are schematic. The best I could find so far is openstreetmap (OSM), with alternative rendering via apps (I use OSMand and Orux maps, there are others).

I am rather confident the landscape in OSM is correct, and the wall is marked right. I was wondering though if anyone can comment on the quality of the trails marked there. It seems the major ones are all mapped - multiple from Xizhazi to different locations on the wall agree with schematic drawings on the web, the access path from the Wofo mountain villa to Jiankou is there.

There is one that is confusing - I'd attach a picture, but cannot for some reason. It starts at the road end about 1-1.5km to the west from the Wofo villa, and runs in northern direction to the wall. It disappears midway to the wall for about 150m, then appears again and joins with the wall about 750m to the west from Jiankou pass. That's between 4th and 5th towers counting from Jiankou, according to OSM. Does it actually exist? If yes, how good is it compared to, for instance, Wofo-Jiankou? Are there others that aren't on the map?