Offline Music Storage & Playback Recommendations

Really a 2 Question Post. Hoping for some good advise....and hoping I placed this in the right category...

I live in a very rural area, cell phone coverage is spotty, and my Wi-Fi is bleak (very bleak as in 2-4 mbps) when it works, so I have built a dedicated audio room (20' by 30') and have a nice "mid-fi" system. I have a Tidal account and have 5-6000 tracks downloaded to my phone which I can play in "offline" mode through my system as well as a large CD collection I often enjoy. So my system and listening environment is basically an offline system. (photos / gear all listed in my profile) 

Question 1) Recommendations for a very nice Music Storage component that I could burn all my CD's into which does not require wi-fi  to operate. Something like the Naim Uniti Core Music Server? It would be OK to have something that operated through an app?, but lack of wi-fi is the issue. 

Question 2) Currently I play a lot of music from my Tidal downloads on my phone, and I simply Bluetooth from my phone to my Marantz 8006 source then from the digital coax out through my Pontus II and out to the Luxman 509X My question is if I would see a significant SQ improvement running from my phone through a nice USB cable (Audioquest Coffee?) and going directly into the DAC vs Bluetooth??

Any Advise is appreciated!