There seems to be some misconceptions from many about what a PC on a stick is.
It is LITERALLY, a full fledged computer on a stick about the size of a Roku stick. They are about $100, but cost varies. They have a HDMI connection, a power connection (USB I believe) and typically a USB connection (I believe). They don't have much horsepower, memory, or much else. They can load and run any and all Windows programs as it is a Windows PC.
So, that's the starting point of this: Stick PCs are still a complete computer. Just like a desktop or laptop computer, but in a smaller format.
The issue comes back to many other questions which should be asked about how you plan to access playback of the content after you have ripped it to your NAS? What type of NAS do you intend to put together? How much storage? Are you just going to buy an off the shelf NAS to use?
The hard part, IMO, is that organization, ripping, etc. requires that you pay attention to the details. CDs don't really have any information on them to let a computer know what is on the disc. The computer gets the track info, length, etc. and then compares it to a database. When it finds a match, it then applies the title to the disc and track info. Sometimes it is wrong. You would need to edit all the information for that disc. This can be problematic, but not a huge deal.
But, you also must buy into a playback solution which works nicely with your ripping solution and meets the needs and desires you hope to obtain.
How do you want to browse for music? Through your phone? Through your TV? Using a remote? Using a mouse?
What quality do you want for playback and what do you want to use for that playback?
Once again, there are tons of choices out there, but if you were thinking a PC on a stick is going to have the same audio quality as a purpose built PC, then that will never be the case.
The hard part is more about finding the specific software that you want to use and figuring out exactly what you want to do. That can be very difficult to determine at the start, and can be muddled with the vast number of choices available in software and hardware.
But, I would agree with others, that a product like the Vault, is exactly the type of solution that fits well into any good setup. It sounds like they have their act together in using lossless audio and allowing for intelligent control. The price may seem steep, but you are buying into a product which doesn't require you to jump through all these hoops you are trying to jump through, to only end up with results that may still make you unhappy, and then buying a Vault in the end because you know you should have done it anyway...
http://www.bluesound.com/en-us/products/vault-2/
Looks pretty good. Not cheap, but all the proper quality and support it should have.
Not sure about their use of their term 'USB NAS' - as those aren't a thing.