Not entirely clear to me. The amount of money that your are willing to put on something is (also if not more) function of your means. I am personally in a state of disbelief when I look at the prices of high end road bikes, often purchased, or so it seems, by wealthy middle-or-no-longer-so-middle-aged guys riding 50kms or less on sunny Sundays, wearing blinding lycras.

hmmm.... one question might be -- what is the ultimate touring bike. Unanswerable, because it depends on what you try to achieve. So it has to be broken down into smaller chunks. Such as -- under what circumstances does it make sense to install a carbon drive + rohloff hub?

Another question might be -- what gives you the most bang for the money, at various price points (maybe you can afford a $250 touring machine, maybe $2000, maybe price is not an issue).

But back to my initial motivation to interject -- people who know very well, may well know that there is no point in paying $4k for a touring rig.