I'm curious too Bayou. Since it's been almost a year since your post, have you made any progress on the # of cores? I have a Gen8 Microserver with a Xeon 1230 v2 running xpenology on ESXi. Just seems like more cores couldn't hurt - especially when transcoding (Plex, etc). I can see 40-50% CPU utilization when streaming mp3s to my phone when outside my LAN.
At any rate, it's a cool setup to be sure.