My opinion it’s all about lowering the noise floor so small things in a recording are more noticeable; when this is done all things will be clearer and less fatiguing. Music will be enjoyable at lower levers as well. In my experience it starts with the cleanest power to feed the components, such as dedicated circuits, receptacles with good contact, then the power cords. I use two different power devices in my system where all things excluding my amp go through a PS Audio P10 and amp goes through a Nordost on its own circuit; both units on their own dedicated circuit. If this isn’t done first then you’re just chasing your tail which I’ve done my share of in this hobby, including trading out components that probably didn’t need to go.
Next I will say it’s room treatment or maybe that should have been first. Between Interconnects and Speaker Cables I start with IC’s and run balance where I can. Depending on the components some cables have more shield than others, (same on power cables) as I’m trying to reduce noise EM/RFI to again drop the noise floor.
Next I would move to speaker cables, and that’s to wrap up the cables and move on to isolation of components and the rack holding my gear to once again, lower the noise floor. Also don’t forget to keep the cables tidy keeping them away from each other if possible. I keep my rack off the wall a bit so my power cables don’t get too close to the IC’s.
Lastly I do use boutique fuses and I do recommend them but I believe for many if their system is not revealing, having a low noise floor, then hearing what they do might not be as transparent. Except for two components I recently picked up I use aftermarket fuses. In every component I have added them it has been an improvement, but not where I would start. Just my opinion.