Streamer vs. new mac mini for 2 channel system

Hi audio friends,

I LOVE the functionality of my mac mini with my 2 channel system: Exasound 62e DAC, Modwright ls100 pre, Coda continuum 8 power amp and Wilson Sabrina speakers.  Being able to navigate with mouse and keyboard from my listening position is infinitely better than using a tablet or some mickey mouse app with my phone.  

The issue is the mac mini.  Clearly this is not the best transport, however I want to use my 2 channel system for more than just streaming roon.  I listen to soundcloud a lot to learn about new music and when I watch tv I want to utilize the stereo for netflix, crave etc.  My Dac has only 1 usb in and obviously an optical + s/pdif, but the fidelity is just not as good with the other inputs.  

I almost pulled the trigger on a Lumin U1 mini, but again I do not see how this transport will improve fidelity, without limiting overall functionality.  How do I bring a new mac mini to a place where it can compete with a dedicated transport like the lumin, or is this even a reasonable suggestion?  

Looking to optimize the system in the most efficient way.
Confused - any suggestions would be much appreciated.