I know at the end of the day yogis aren't keen on intellectual philosophizing, but in any case did Yogananda ever happen to mention which of the western philosophers he felt to have, compared to the others, the most realization or wisdom?
I’m not sure that Yoganandaji had much to say about Western philosophers. I suspect he would have said, as Swami Kriyananda has often said, that love of wisdom (the literal meaning of the word, philosophy) is far inferior to wisdom itself, and that wisdom comes only through direct experience of truth, not through the intellect.
The Westerners who Yoganandaji felt had some realization were saints, not philosophers. Noteworthy among them would be Saint Francis of Assisi and Saint Teresa of Avila. They experienced truth. He also praised the book The Imitation of Christ, by Thomas a Kempis,