How to drive yourself insane

It started out so innocently...  I have a CA 740c player/dac, a dedicated Mac Mini playing files through Audirvana, feeding a B&K Reference 5 S2 preamp which feeds a Rotel 1080 which finally dumps to Focal Aria 926 speakers with a Gallo TR2 sub.  Decent interconnects and power cables (Morrow Audio mostly on the ICs), al that.  Nothing fancy.  The 740c's transport was skipping so I sent it off for repair and it didn't come back for over a month.  I lost the DAC for the Mac and CD play capacity.

I get impatient and wonder what's out there.  Audiogon was so seductive.  I try to do my homework reading up on DS vs multibit, DAC chips, upsampling or not, interconnect limitations per source, etc. and never could get to the bottom of just how much better an 800-1000 dollar DAC would sound than what I already had.  Yes, Schiit offered a 14 day trial and when I got my deck back I intended to do an A/B comparison with Schiit Bimby, but all the reviews and such, along with the technical pages, never really gave a clear differentiating message to make it worth exploring.

I ended up ditching the optical input from the Mac, which had a limitation, for USB out to a Schiit Eitr box which provided RCA out to the 740c, which had no USB input.  So now I can pipe 24/192 FLACs to the 740c which upsamples to 24/384 like it or not.  Sounds good, but what would sound better?

This has me wondering if a better DAC would make a difference given the limitations in my system.  I see $10K DACS and wonder what on earth they need to sound their best and differentiate from a $1K NAD DAC I see on Audioadvisor.  This is the rub that necessitates audition - the DAC is but one part in a signal path from source to speaker, and who knows what impact downstream components will have.  No one can tell you with any precision so you have to buy on faith and try to not succumb to placebo effect, or hunt for a trial.  In my case, I don't know that the Schiit trial with restock fee has that high a probability of a 'wow' factor that would make purchase imperative.  So, I vacillate between cold comfort of knowing I've made the best of what I have, and wondering if a Bimby w/o any upsampling voodoo would really sound better than the 740c, and asking myself it it would be worth the freight and restock charge to find out.  My real problem is I don't have the money to buy/sell components and have a more or less perpetual audition system.  How can you finally say "enough!"?