Best bang for the buck upgrade path for Mac Mini

Been a few years since I was a regular contributor here and a lot has changed.

I am going to set up a Mac Mini running Amarra as a dedicate music server. Will be a 2010-2011 build with 8gb RAM and a 120SSD. I have a couple of thousand CDs ripped to AIFF and AAC which will live on an external 3Gb 7,200 connected by FW800.

Will use the Mini to feed my Oppo 105 and then use the analog outs. Planning on using a 7" USB LED touchscreen and the built in SuperDrive to manage ripping, then disconnect the display. Perhaps not perfect but I hope helpful for calibrating your response.

Seems to be two ways to go with the Mini. One is to use something like a Keces or Mojo to clean up the Mini power supply. The other is on the USB output side - either cleaning the USB output up and going in to the Oppo async, or converting it to SPDIF which the Oppo also handles like Halide or Audiophileo.

Not doubting that someone will say do them both but I can't - at least not now. Much as I admire it, this is not a CAPs build.

Based on your personal experience, where do you think I will get the most bang for the buck.

Are there alternatives that are synergistic that I should consider?

Thanks in advance for sharing your experience.