Welcome aboard.
Great question, most never get beyond the eye candy of big shinny gear. I refer you to Floyd Toole's "Sound Reproduction"
IMO after speakers, the most important factor to good sound is having a proper room. Considerations should include (in order of importance):
1.) Shape (avoid simple ratios of primary room dimensions, 1 x 1.6 x 2.6 is a good one)
2.) Size (within good shape constraints bigger is better, ceiling height normally being the limiting factor)
3.) Control (man cave concept to listen when you want, decorate as you want)
4.) Isolate (separate framing, insulate to reduce sound transmission in/out including ventilation and electrical power)
5.) Treatment (in a well shaped, large, dedicated, acoustically isolated room with near-field layout the need for treatments can be minimal)
My 8 ft x 13 ft x 21 ft basement study scores a solid 4, bigger would be nice but not realistic, builder screwed me out of more ideal isolation.
