Well, plenty of things to say about your questions. To make it simple.
I use ROON ROCK on a self build NUC I called FRANKENSTEIN, you can read about it in the « Café » items.
The only item I change in the ROON DSP settings is the Crossfeed filter when I listen with the cans. Otherwise I leave all the settings unchanged.
For the settings in the Aries G1 and the Mytek Brooklyn DAC it is somewhat different. I will give you mine in the following posts.