A lot of complexity in this question. In my mind there are 2 fundamental different ways to listening to music on a reproduction system: 1) you can listening to the musical idears ("Hey listen to that baseline. Listen how she waits a quarter note before she ends on the G") an 2) you a listening to The Illusion of the performance ("Now listening carefully how the the instrument behind the guitar moved back a little and suddenly separate! You hear it's a clarinet?")
Both ways of listening will improve when you upgrade, but only the latter is critical.