Thanks for writing this all up! FWIW, I have gone that NAS route in general though with TrueNAS (formerly FreeNAS), I didn't like Synology myself after trying it. I think remote access works better if you just do it via modern VPN. Wireguard has been incredible for me, and there are options like ZeroTier and Nebula for more advanced automated meshing and so on. For me at least I've found it better to have less vs more in a given component, so the NAS is focused pretty purely on storing and making available data and that's it, network services are all done elsewhere (in OPNsense for me), same with VMs. That keeps things much simpler (admittedly for HN-values of "simple"), the NAS and various other services can simply act purely as "LAN". Also makes it easier IMO to keep things better isolated and secured by avoiding any public WAN exposure except for VPN ports (and even that can be further offloaded with a cloud-based bastion or the like). I also just made my own internal CA, which means I'm free to set certificate lifetimes for 10-20 years if I want. Linux/BSDs of course are straight forward to add your own CAs too, and least with Apple devices as well it's super, super easy and free to make up a mobileconfig profile containing all CAs/certs and various other configs, then install is just a few clicks that even non-technical users can follow. Let's Encrypt is certainly cool and easy to setup in OPNsense but I don't think it's necessarily ideal for purely internal services with nothing public facing.

100% agree however that documentation is often lacking, though the OPNsense and FreeNAS docs remain pretty good.

>And regarding your last point, I also generally agree! Although it feels silly to me to have a NAS at home and then still do regular backups via another storage/backup service elsewhere. I wouldn’t want to back up 1+ TB of files every day or even week, although there might be diffing solutions for that.

Every backup solution I know off only syncs diffs, that's pretty table stakes for precisely that reason. For units that support snapshots, there are also plenty of controls for dealing with snapshot lifetimes and pruning. All of that certainly still is more upfront to setup however!

I think the big reasons for the expense and effort of a NAS though are mostly down to if you can/will make use of the speed and scale advantages. The security aspect might be a bit of a wash, one can do E2EE anyway with a typical cloud provider, and while they're more publicly exposed they've got much more serious effort behind them too. At 1TB it's probably not worth the effort. But other options definitely get more expensive as one gets into 10-20+ TB, and the value of more serious data integrity and snapshotting and so on too. 10 gigabit and even more is also getting quite reasonable to do on LAN, it's easy to saturate these days, and particularly for those of us living in rural areas with mediocre uplinks that can be genuinely handy.

I feel fortunate to though to live in a time when we all have so many options to meet our exact needs. Possible for a home or small business to put together options now that would have been top end enterprise stuff not that long ago.