Welp, interesting development.
After doing some reading and seeing if I actually could eek out enough space to backup the server onto my PC, I discovered that one of my two RAID 0 drives is failing with uncorrectable errors (timing couldn't be worse) . In the interest of getting the data off the array ASAP (I have no idea how long it's been like this) before loosing the whole thing (the bulk of my game library) I'm putting the shucked drive in my PC. I'll have to get another new drive to use as parity. I feel better about leaving a brand new server without parity for a few days than hoping a failing drive will last until I get a replacement.
Thanks for the help though. In any event I learned a lot of things I wouldn't have otherwise.