Worth a look, any Intel CPU with onboard graphics that's not horribly old will have quicksync on its iGPU.
MangoPenguin
I dunno if there's an iOS equivalent but on my Android phone I use the WG Auto Connect app so it's only active when not on my home wifi.
I generally just make notes in Obsidian, mostly about switch ports, VLANs, IP assignments and that kind of thing.
Also try to save snippets of commands or config edits I needed to get something obtuse working in case I need to do it again later.
My solution is other people in the house don't rely on anything in my setup, other than the router which runs some basic telemetry and fraud/phishing domain blocking but that's all.
They cost about $2/month at the average power rate in the US, so it's too small to notice I imagine.
I've used a RV/Marine deep cycle battery attached to a UPS before, that would certainly give you enough for 2-3 hours on most setups.
Have a look at Backrest for Restic. It works great with pre/post scripting and supports healthchecks for monitoring status and stats.
Also is a nice easy to use WebUI which is great for servers.
It should be the same setup regardless if you're using a VPN or not.
Having used both I generally prefer traefik.
Does it have QuickSync support? If it does it might be able to handle a few 4k transcodes.
Alternatively I wonder why the video is needing to be transcoded in the first place, maybe you can get it playing natively.
Wireguard is where it's at.
Latest thing is my server was hard locking up randomly every couple days. Finally thought to check IPMI and it was triggering a correctable ECC error on a specific stick of RAM.
I figured maybe the first couple errors were correctable by the ECC RAM but then they just got worse and caused the lock up.
Pulled the 2 sticks in that pair and so far so good. I'll survive just fine with the remaining 192GB of RAM lol.
Also switched from my old Dell box with Opnsense to a Linksys MX4300 running OpenWRT, saves me about 20W and its fun to try something different.
Power back on needs the BIOS set to power on after power failure, the UPS will shut down after everything powers off, so the power coming back on will start things up again.