Your remark about the confessional quality of The Philosophical Investigations is exactly my take as well. We don't argue with poetry. You can like or dislike The Wasteland, accept its view of the world or reject it, but you can't really argue with it. It's simply there like a Surat painting. In Culture & Value (I think) W says that philosophy should be read / written like poetry. In any case, your personal, passionate & confessional response to Wittgenstein is a recognition of his--& your--poetic qualities.