When I first started helping with this we used to do the training, Night-O and everything else on a 1:15000 map! The beginner stuff pretty much stays in the camp, which was about a total of 2 x 2 inches square on that map. I was so happy when the 1:5000 came out.
I had trouble reading all the detail in the camp area on 1:10000, using glasses and a magnifier (I think I mentioned that). I cannot even imagine 1:15000!!