I just asked a very similar question over here: https://reddthat.com/post/29255208
Where I had put together a proposed self build and looking for feedback on it.
I've been running Unraid for a few years and it's been great and really user friendly as well.
You mention about getting an AMD cpu, and I've heard similar stories about Intel quality lately, however I've also heard in the past that AMD cpus aren't very good at going low power. Electricity is expensive and I want it to idle as low as possible. Plus for my build, I'd certainly make use of quicksync on an Intel CPU.
https://uk.pcpartpicker.com/user/Nutbolt/saved/#view=rrchkL
Any thoughts as I'm looking for opinions on the intel vs amd but also on my proposed build. Thanks