And my point is to make it small enough in order not to deal with all that complicated psychoacoustic stuff, which we can't properly sort out and which results to marketing speculations only. Why you insist on keeping the distortion, no matter what kind of, if it can be eliminated completely?
I've advocated no such thing. Why are you making things up? Now I"m the one "keeping the distortion" after you told me that I can't back out linear modifications, which is quite possible! I'm the one saying "back them out if you must have them", so now I'm "keeping" them? You are simply having an argument. Stop it.
And, no, you can never COMPLETELY eliminate error in any analog system (or digital system with any substantial processing). Never. Physics prevents it, and the level of noise due to physics is, you will find, surprisingly close to limits you might want to reach. Ask anyone who's built a mic preamp or an LP preamp. (p.s. that RIAA EQ in the LP preamp is a classic example of backing out a linear modification, you know)
There is no such problem anymore, both DeltaWave and Matlab code removes time inaccuracy with ease. This is deterministic operation and can be done with any predefined accuracy.
Yes, yes, including partial sample alignment. Been there, done that. Over and over. You have bothered to go to the site I pointed out long ago that's the "fft workshop". It has octave code there that, among other things, will measure delay to an annoying accuracy (especially annoying when some folks latency claims are examined, not your problem).
3d plots of error signals are not what you need. You're still not plotting error (as a function of time and frequency) compared to SIGNAL as a function of time and frequency. Everything you talk about is signal dependent. You did notice that I said for a normal listening room with normal equipment, 110dB total SNR is probably sufficient. That assumes room noise and a peak limited system equal to most "hi fi" systems. A PA system for a large space will require more.
As to software that's available, I've probably written some of what you're using. Certainly I've written many linear-system identification routines, detection of distortion product routines, etc. Goodness. Now you're not only condescending and putting false words in my mouth, you're telling me to go refer to my own work? SERIOUSLY, dude?