I feel like the dark blue spot north of Trier should have some train station in Luxembourg or Belgium that is actually closer than the nearest German one. Is there a way to check that?

Do you have a link to that data, too? Because the one you posted in another comment (https://www.theglobaleconomy.com/rankings/pharmacists_per_1000_people/) doesn't correlat to anything shown in your graphs at all. There is only data from 2 Asian countries (South Korea and Israel), 20 European ones, as well as Canada and Australia and New Zealand. And the values range from 0.2 to 1.3 not in the double digits like in your graphs.

What kind of categories are that?

You divide Asia up between Eastern Meditteranean (btw. Morrocco is as west as you can get in the mediterranean (even more than Algeria, who you put into Africa), but ok), South East Asia (why tf is one of the Koreas in that category?) and Western Pacific, but then lump Uzbekistan and Turkmenistan in with Europe? Also, how tf is Cambodia Western Pacific, but Indonesia and Timor-Leste are not? Have you ever looked at a map?