The controller does not need to run 24/7. The controller configures the devices and the config remains on the devices. Though, when your devices are adapted by a controller, you cannot access any settings on the devices themselves, only via the controller.

Maybe should add: depending on the network set-up, I'd strongly recommend getting a hardware controller. For me, I have one server hosting all my stuff. I also hosted the controller with docker in this server. Which ends up being a single point of failure, and no way to look into your routing if your server is down/unreachable. I got a hardware controller (oc200) eventually just to separate my interner and network infrastructure from my hosting and service infrastructure.

I am very happy with my Omada setup. It's an ecosystem, not a single device. I use an er605 as router and eap610 as AP. I also have a switch, probably you don't need that, and I now have an Omada controller (you can also host that in as a docker container, so not strictly needed). For wifi you can simply throw another ap somewhere and have excellent Mesh wifi. It's more complex than a simple consumer router, but also has a lot more functionality.

Out of curiosity, why would that be a problem?

Maybe have a look at urbackup. Gui, "centrally managed", free...

And please, as mentioned in another comment, have a look at Borgmatic. It makes Borg really easy to use and has some super handy features. Super easy backups to multiple locations by just adding a line in the config... And I just love the healthchecks integration. Set and forget until either healthchecks notifies you of a problem or you really need to recover data.

Can confirm Borg/Borgmatic. Was looking for something good also and Borg is hands down the best. Borgmatic is kind of a wrapper for Borg which makes things even easier. One thing that makes Borg awesome is it's excellent documentation. Maybe give cli tools a try ;)

I tried fenrus before, kinda liked it, but I remember it to be not so performant.

I had authentik before but I found it to be unnecessarily complicated. Its really a nice one stop shop, doing authentication, authorization, even reverse proxing, but the setup/UI is just ... Not very well designed. Or it's so advanced that it's very far from the no it background hobbyist user

And how do you disable the editing/configuration in Heimdall?

By no means an expert, bit I'll try: One technique would b asymmetric encryption. Every participant has two keys, a public and a private one. When I want to send you an encrypted message, I encrypt the message with your public key. This key you can make available in any way, it can't be used in a harmful way. The message I encrypted with you public, you can decrypt using your private key, and only with that. Like this, you only need to exchange public keys used only for encryption. So no useful information for an attacker. And private keys never need to leave your hands.

Probably it would be much easier for you to setup tailscale. Just install it on the system you host the other services, install on the other end and use the tailscale ip. It should require minimal effort to set up with the added benefit of not having ports open, and way easier maintaining.

As for wireguard, the allowed up section tells what ips should be routed through the tunnel, it's not that difficult, but hard to wrap your head around at first. A friend of mine also used to use the Fritzbox Implementation of wireguard and I remember you need to specifically setup what clients you want the tunnel to have access to.

Have a look at tailscale.

To follow up on this: I now use a combination of caddy as reverse proxy and authelia for authentication. In my opinion caddy is the best reverse proxy, it's super lightweight and the caddyfiles are super easy to read. Authelia is surprisingly easy to get setup. I was a bit hesitant because it looked a little overwhelming in the beginning. When you sit down for half a day and dig into it, it's really surprisingly straightforward.

It really does look cool. It can be deployed using Docker. I'll have a look at it.