Hi superstoked, I’m not an authority on DAC’s by any stretch of the imagination, however I run a Node 2i and a Node 2 in both my systems. Within the last couple of months I dipped my toes in the external DAC waters. I run an April Music Stello DA100 Signature in the main system,and a Beresford Bushmaster in the secondary system. Both are not top of the line,and both older DAC’s. That said,I’m still very happy with what they have to offer. I noticed more detail,and definitely a much,much larger holographic soundstage on both. I can only imagine how much better a newer,and higher end DAC would sound on either system. Like you,I was running the Node products via rca analog out. I was very happy with the SQ.( Ignorance was bliss!) Keep using the DAC in your pre,since you have that option.
Best of luck!
Best of luck!