I am surprised I didn't see anyone mention there is a commercial blade solution (finally shipping now after what feels like years in kickstarter)
https://www.kickstarter.com/projects/uptimelab/compute-blade
OPs package is very cool though.
the power coming out of my walls is terrible. really unpredictable, constant brown outs, and storms impact it badly. At the least a very small UPS will even out and correct the power. I've had electrical storms take out computers, firewalls, a TV, and a dvd player. Everything on my house is on at least a surge protector, servers are on dual UPS, on two separate circuits, my PC is on a battery, so is the internet gear, separately. I hear it at work frequently. We also have a whole house surge protector. I'm just outside a major metro. invest in UPS.
BTW if your pi crashes while writing it will almost certainly corrupt the SD card beyond use. I have moved to SSD or netbook (PXE) because I got tired of replacing the damn things.