Why did you choose the components and speakers that are in your system?

Cost/benefit ratio.

IMO, Other than DIY, highest was speakers (pairs of Quad 2905's); lowest was cables. Still haven't spent enough to justify cables better than those based on Canare Starquad microphone cable. Maybe after the second Koetsu I'll take another look  ...  YMMV

Can you setup Open Baffle speakers in your listening area?
They need to be 5-6 feet into a room. Conventional speakers 2-3 Feet.

If your current speakers have 6-8" woofers and have the room size required you might get the Spatial 15" open baffle speakers and really
appreciate the difference.

Or as suggested try some electrostatic or planars

Furman 20 PFI - protection + clean power without loss of dynamics
Airport Express - to transfer data only (computer not important)
Benchmark DAC3 HGC - to make 280ps of AE jitter inaudible.
Benchmark AHB2 - very clean and very dynamic.
Hyperion HPS-938 - Giant killer speakers.

Trial and error. 

Accurate speakers provable by measurements instead of cognitive bias. Electronics that are adaptable to automation and streaming, and under the threshold of audible distortion. Speakers that compliment  the rooms they are used in. For example, I need unobtrusive speakers in the living room, but not in the media room. Flat down to 31Hz (5-string electric bass). Price.