I am feeling more and more vulnerable with all my digital content, and think I may install the server above at a family members
A good start, but the server alone is only half of it.
Having a good off-site backup operation plan, as well as successful execution of it is also vital.
Most digital video & music can be re-downloaded, ripped or purchased... photos and old code are the two things I'd hate to be out... so I have two external HDs which I backup the key bits from my home server to every week, then rotate the two back and forth to/from the office on a rotating schedule.
The bugger with such a plan is proper diligence as it is easy to forget to do for a while... something I shouldn't do as the apt complex I live in has had two fires in the three years I've lived there (one requiring the demolishing of a building (1 of 8), another happened inside of my bedroom wall).