@8th-note I am right with you on the not hearing any significant difference between my computer to the DAC and a much higher cost individual streamer/more expensive DAC combo.
I read some posts on this site about the use of a DDC. So I bought a DDC (Denafrips Iris) which I tried which was a greatly lower cost tweak. I believe (can't be sure because I can't AB test it like I did computer/old DAC vs. expensive DAC/separate Streamer) I am hearing some significant differences such as clearer more pronounced bass and some detail without the digital glare in the upper range. My belief is enough to feel that the sub $500 cost was worth it.