I think the main difference is the contrast between the colours. Current map everything is bold and in your face and so blurs into one. On the old map the black is darker so stands out but the yellow and brown being slightly more subtle mean that its easier to pick out the detail. The old map is not much less detailed.
So probably a printing issue then, I thought the map was pretty clear - just some small sections in the SW I couldn't read and run
I don't think its printing. I think the colour standards and mapping defaults in OCAD are to blame. When you have elites retiring almost from the start because they couldn't read the map and having the technique run on a bearing to the circle and search/hope, something is wrong. I can only think you must have exceptional eye sight if you didn't have any problems.