Using this on the top 15 German authors from VSI: (still using English language, 1900-2000)
1. Goethe >> Schiller >> the rest of early ones up to Heine
2. Among later ones who are primarily referred to by both names: Thomas Mann >> others
3. Brecht > Kafka > others (using single names); but here Brecht maybe too common that may help
4. Now if I try single names: Mann > Goethe > Schiller ~ Brecht > Kafka. Now of course Mann at least has two persons - Thomas and his brother; and many others who came afterwards.
On the intellectual stars:
5. Among first 7: Kant and Luther led in this group (Eckhart, Luther, Bohme, Leibniz, Herder, Kant, Mozart, Humboldt)
6. Among the next group of 8 clearly Marx led (Schelling, Hegel, Fichte, Schopenhauer, Marx, Engels, Wagner, Nietzsche)
7. Among this next group of 10 Freud led by a big margin (Freud, Jung, Wittgenstein, Heidegger, Marcuse, Strauss, Fromm, Horkheimer, Adorno, Habermas)
8. Now try the all-star list:
1900: Luther > Goethe > Kant >> Mann (of course!) > Marx >> Freud (also clear!)
1950: Marx >~ Freud (whose stars shot up post WWII) > Goethe >~ Luther > Kant > Mann
2000: Freud > Marx > Kant > Luther > Mann > Goethe
Note that these results probably are badly skewed because of my not using transliterations ...
But this suggests in my list of 150 (remember it is pre-1900 by design), the inclusion of Marx, Kant, and Goethe was alright. The miss is that Luther should be in by Calvin out; and inclusion of Nietzsche is questionable.