The problem to me with tweaks, is that just changing a system can make it sound better. I believe we are attuned to changing sensory input, any change may sound better. For example, before I saw the error of my ways and bought an ARC Ref 75, I used 2 very good integrated amps. Whenever I switched from one to the other, it sounded better, whichever one I changed to.
Accepting this and the desire, hope that there will be an improvement,so you hear one, then this is where I hear a difference. I would say in all the major components, amps, CD players, speakers etc. All the elements of a wiring loom, including PCs, I am sure I can hear a real difference. Knowing if it is better or just different, can be more difficult. I am sure, cones, supports make a real difference, distinguishing them, more difficult. Cone A and B both help, which is better, I really find difficulty with.
As others have said, With some caveats and qualifications, if it sounds better, it is better and don't lose sleep over it.