IMHO (not a fact, just on opinion ) listening to many systems is enjoyable and we can learn about the limits of equipment and sound reproduction, but is of little use to know in detail about equipment. It can help to learn about our preferences if we do not have a firm idea on them.
Again IMHO there are no "best" rules to assemble a system. The variables are too many. We must find some equipment we trust in our minds and get it at home. Then move on assembling a system.
Most high-end equipment has excellent sound quality. A good part of it not compatible with our preferences and way of life. IMHO if you have to travel a lot to listen you should consider such equipment with care - a good friend just spent more than 100k in a complete system and is now waiting in silence for a visit of the seller in June to solve a problem. And yes, he traveled to listen to it ...
One statement in this post from you I would disagree with:
"Most high-end equipment has excellent sound quality."
IME, most high-end equipment has rather mediocre sound quality despite the high price, which is primarily for luxury purposes. Very little of it sounds remotely real, even with the best recordings.