

Do not use an SSD for cold storage - it will fail. SSDs need to be plugged in every once to refresh the charge in their NAND, otherwise they’ll lose the data.
This is not a theoretical thing - I’ve had a good Samsung 850 Pro drive fail while being off for 2 years.
Yeah, this might be the way to go. OpenWRT supports hardware NAT with many of these ARM-based routers like many of the MediaTek-based ones, which gives them super high throughput at very low CPU usage. The efficiency blows x86 out of the water. The ability to migrate your OpenWRT config to new hardware (real or virtual) in the future means you kinda get the best of both worlds…