It's surprisingly consistent, though of course there are plenty of exceptions and imperfections in the analogy depending on the language.
And I agree that those icons wouldn't be helpful, just that there are certainly better examples of "list of things with no easily assignable symbol".
Nothing wrong with Nordic roots at all! The "bastard language" comment was meant in the sense that modern English is a germanic+romantic mongrel, so the link between our words for days of the week and our words for the planets don't make nearly as much sense as they do in other languages.
that's honestly not the best example, because, in many languages, the days of the week are associated with the planets, and all the planets have a well-recognized symbol associated with them.
with french in parentheses since english is a bastard language that uses nordic variants for half of them:
native english speaker here. 93/100, also just got lucky on a few. Interestingly, i missed the most in the "advanced" section, despite that being the middle tier... I guess weird words stick in my head better? There were a couple i missed where I apparently learned the word via context-clues while reading, but with the total opposite of the true meaning, and just never noticed, lol.