It's always good to talk with you, but I always seem to arrive at the same point. And that is, I can't really put my finger on any substantial disagreement between us. Of course we have had very different life experiences and we see the world through those filters, but except for my awkwardness in trying to express myself, I think we see pretty much eye-to-eye.
I think my understanding of the word 'mysticism' is the same as yours. It's just my poor writing that might give you a different impression.
The piano example is interesting. I am also an amateur pianist (I have just started working on the Waldstein, which is way over my head, but can still give me that spiritual feeling you mentioned even though I can't play it at all). Rather than any of my own experiences, the one I marvel at is the guy who was blind, mute, and severely mentally handicapped but nonetheless was able to play the piano after hearing a piece on the radio only once.
I saw a TV documentary about him which gave a good picture about what he had to work with and to me it is one of the most convincing pieces of evidence that there is something transcendent at work in our minds. In cases like this, science has a lot of explaining to do.
Another, more common, example is the way children acquire their initial vocabulary. I don't think there is a good scientific explanation of how they are able to do that. But, of course, there didn't used to be a good explanation of eclipses either.
I think we have a lot to talk about, Aurino, but nothing to debate.