I’m an arch user, and also have a small proxmox based homelab. I always have a live Ubuntu around, the latest desktop version available. Good for troubleshooting. Also, latest proxmox, opnsense, pfsense, debian.
Additionally, I have a small USB drive on my keychain with both USB C and USB A, where I keep some encrypted backups of important stuff, and I can access that from both my laptop and my phone.
Yup, I have a domain I purchased and on my lan I use PiHole and Caddy. All my apps and services use the format app.mydomain.com. PiHole forwards all requests for *.mydomain.com to Caddy, which handles the LE certificate (via DNS challenge) and forwards the requests to the proper IP:PORT. I started using this for everything, my Proxmox hosts, printer, my APs…
Immich does have a pretty robust user management… https://immich.app/docs/administration/user-management/
Not only for Nextcloud, but I recommend setting up crowdsec for any publicly facing service. You’d be surprised by the amount of bots and script kiddies out there trying their luck…
I used to have everything backed up to a 2TB USB drive. Which I accidentally dropped down the stairs. I lost thousands of family photos and documents. That changed my backup perspective.
I now have a Synology NAS, with 12TB in a RAID5 array (for a bit of disk redundancy). All my home devices, Proxmox servers etc back up here. The NAS also holds a few TB of media. Attached to it I have a USB hard drive (also 12TB). The NAS gets fully backed up to the USB drive nightly.
I also have a remote Raspberry Pi with a smaller USB drive (4TB) attached to it at my brother’s house (in another country), where I backup most of the contents of my home NAS. I don’t back up the media, just the important stuff. I might have to upgrade to a larger drive…
We’re using a self hosted Nexus instance at work. You probably don’t need all the features it offers, but it does its job really well. For free, too.