1. this is one of the coolest maps I have ever seen of anything. 2. it has me thinking about a legible or elegant way to encode the antipodal pairs. maybe with some kind of cyclical color scale? what works for this sort of thing? 3. is 2 already implicit here? can you just follow the graticule in some intuitive way to find the antipode of, for example, the isolated red area in (I think) SW Canada?

I think that point is the TAAF (French Southern and Antarctic Lands). The non-traditional projection makes it a bit difficult to follow, but I'm not sure if color would help much either. Having a pop-over when you click on the map, that shows both antipodal locations could be fun.