Not planning any experiments . . . I hope to upgrade the crossovers exactly one time! Or piecemeal, given that I already have the Clarity SAs in the coax feed. ie, start with the woofer feed, maybe put newer Clarity (or Mundorf) in the coax feed as budget and nervosa dictate :)
From Tom's posts, the best bang-for-the-buck could be to "simply" put top-shelf bypass caps in. I might look at options from Cornell Dubilier in addition to Clarity and Mundorf.
I will continue to check this thread for more info from Tom Thiel and, hopefully, Rob Gillum. In the meantime, there is no doubt that the music in my living room is more clear, immediate, and involving than ever. And I want even more of that!