Best DAC for my system?

Yes, spend more.
No. not a fortune.
$1,200 will do it.
Buy used.

Benchmark 2 or 3.
Chord Qutest

Worth it.

Spend a bit more for a MHDT DAC, R2R, non over-sampling, no digital filter, no op-amp with a Tube :)

I have created a separate linear power supply for my Khadas tone board generic edition, and I bought a Nordost USB cable.
Well... this combo greatly improved the sound quality of the Khadas.
I have done 2 blind listening tests with friends, against the Schiit Gungnir and the Denafrips Ares II.
Nobody, I mean nobody was able to identify the Khadas. LMAO.
So clearly the winner is the Khadas tone board generic edition if we compared the sound quality and money.

Have you tried the DAC on the MX119? That would be the first thing I’d try. If you still feel you need an external DAC, I’d suggest upping your budget, plus consider used. 

crn3371..yes I compared them and the Node 2 sounds better.  The MX119 was a little dull and not as defined.  Thanks for the suggestion though.