So 3+ years later and very little has changed with this server. The UPS is on its 3rd battery now, which is ok by me since its cheap insurance.
The server has been running flawlessly for all these years, with the only issue being a fan that has started making noise. Overall I'm very impressed with the entire build. It's been rock solid, through various unRAID upgrades, a house move, and frequent streaming (I have 3-4 remote streaming users on my Plex not including in house streaming).
Space still hasn't been an issue for me. I frequently go through the files and purge