I have Chesterton. I love Chesterton. I like Father Brown as well. Chesterton was insightful but I do not think of him as philosophical. He is more accessible than Pieper but I do not think he is as insightful as Pieper.
Btw, you can find real treasures (and they're free!) on Internet Archive. I think they have Pieper's work on the virtues. A lot of Fulton Sheen (audio and text).