Dominic.
I would say from reading above, you're on the path to digital audio Nirvana...bar the Dac
Multiple external drives..esssscellent Raid is aptly named, every now and then it does just that. I had it for gaming and Raid did all the playing.
For audio only with a nice readable music player and tweaking potential that isn't too fussy regarding hardware; Lubuntu/mpd/DeaDBeef. You'll have the option of streaming.
Voyage/mpd/mpc is great IF you have the right hardware and don't mind having two computers running, albeit one may only be hand held.
Nothing wrong with Win7 in Hog mode but why have an all singing all dancing OS if you're going to keep it in at night and strip it of its dresses, dancing shoes etc and keep it in the kitchen (?)
Add to that Prince Charming will have to move in to stop her wanting to go out at night and as you've found out, the Prince costs
Course,once you've got it all sorted the writing of a guide of how you did it in English is mandatory.
Single spur balanced Mains. Self built music server with 3 seperate linear PSU, Intel i5, 16 GB RAM no hard drive (various Linux OS). Benchmark Dac2 HGC, single ended XLR interconnects/Belkin cable. Exposure 21RC Pre, Super 18 Power (recap & modified). Modded World Audio HD83 HP amp. Hand built Monitors with external crossovers , Volt 250 bass & ABR, Scanspeak 13M8621 Mid & Scanspeak D2905/9300 Hi. HD595 & Beyer 880 (600 ohm) cans.
The whole problem with the world is that fools and fanatics are always so certain of themselves, and wiser people so full of doubts.
-Bertrand Russel
John.