Looking forward in seeing the final product James.
I currently am using a pi as my Squeezebox server (my 70k FLAC files are located on another NAS). It is working fine, as I mentioned the music is on a external NAS , but the pi is running the server S/W, and I even installed the squeezebox player software. It is currently is supporting 9 different squeezebox's throughout the house.
I built a 2nd pi for my hunt camp, It too is running both the squeezebox server & squeezebox player S/W, it also has 25k MP3's on a thumbdrive. While I don't have Internet access at the camp, I installed wifi access point S/W on the pi too, so that I can use a old iPAD as a wifi remote control. I have been playing with a HiFIberry amplifier/DAC daughter card , so I can connect speakers directly to the pi. It has turned out to be pretty neat little integrated system that is twice the height as a deck of playing cards and will run off of the 12V DC power we currently have at the camp. I am not sure how robust the amplifier will be when the "hooligans" show up and want to party however........