Low Cost DACs

The thought process / flow is correct for improvement.
USB / Coax would be a preference.
Note that differences (at the PC) in "Sound" will be heard from one brand to another.
Mac difference once again.

Is the Multibit Sound Better? Yes!
At $150 difference would you regret the Multibit choice?
Especially if you keep the DAC for 2-3 years.
The Gungnir DAC's, Multibit / Delta-Sigma are the model's that I have had for use with two shiit.audio head-gear Amps.

wcc10, Windows is not detecting the USB connection.
"Please Connect The Cmedia USB 2.0 Device."
Disconnect the Modi DAC. And uninstall the drivers that you installed.
Restart after each uninstall / install with Windows 7.
After Uninstalling any installed drivers Reconnect the Modi USB Cable
and see if Windows ’detects’ Schiit USB Audio device.
If Schiit Audio USB Device is not on the ’Playback’ List then proceed to install Gen 2-3 drivers from the link on Schiit Audio website Downloads.
Links for three different versions ( v 1.16, v1.03, and Gen 3 ) for Windows 7 / 8 are available at schiit.com / drivers.
Please refer to Schiit Downloads Page for procedure and troubleshooting.
To check this open Sound > Playback Tab in Control Panel.
If Schiit USB Audio device is on the list be sure to select and Set as Default.
>> Important <<
Also check the Properties setting.
Control Panel > Sound > Playback Schiit USB Audio device > Properties > Advanced TAB > Select Format Sample Rate and Set the Sample Rate
to 24 / 192.
The Sample Rate Setting in Windows will effect the Output!
Also any Player settings! As per Schiit’s notes.
Gen 3 Drivers are necessary for Schiit’s Unison USB hardware and likely would not impart any difference in Sound.
This is sNeezy eZ no trial or tribulation is necessary.

Not 'redundant' if used at all ...