Next Best Upgrade for Tidal MQA?

I’m trying to decide what my next best upgrade is going to be to improve my streaming music quality (predominantly Tidal, and Tidal MQA, when available).

Current setup:
Custom Deep Sea Sound 18” subs (2)
Marantz SR7012 AVR
Bluesound Node 2i
MyTek Liberty DAC
Parasound A21+

I’m wondering if I’ll get a bigger jump from inserting a Parasound JC2 BP as a pre-amp or replacing the DAC/Streamer with a MyTek Brooklyn Bridge? Or is there something else out there in the $2500-4000 range that will help make a significant jump?

Help and thoughts appreciated!

I guess I should also add to the list the Manhattan II with Network Card, although that would be a bit of a stretch.

From digital coax or optical 
When streaming MQA content there are 3 unfolds which must occur to receive fully rendered 192khz/24-bit MQA. The first of these unfolds is handled by the BluOS app and will output up to 96khz/24-bit audio. The next 2 unfolds are handled by the internal DAC of the Node to provide 192khz/24-bit audio.
If you have an MQA certified DAC connected to your Node 2i, you can enable this MQA External DAC option to have MQA content pass through the Node 2i untouched and allow your external DAC to handle all 3 of these unfolds. 

As for upgrade.. Good preamp makes difference but not sure inbuilt dac gives best result or future potential. I would say a seperate might be more sensible choice
Here are preamp, streamer and dac to check out or read up on. Someone mentioned the Schmitt Freya which runs 6sn7 tubes is a great suggestion. Also mentioned was PS Audio. I owned a PS audio PCA-2 preamp with outboard power supply and thought it sounded better than many tube amps I've owned including BAT, Bruce Moore, Audio Research plus others. I think the ps audio stuff sounds like tubes it is a little colored in a good way. For a dac check out chord qutest, RME adi2, Orchid, Denafrips, Musical paradise. Streamer an old Auralic Aries mini or Aries or lumin mini would all be nice. If you going to spend your hard earned money take your time.