Outside ring a unifi ecosystem is going to be your next best bet. I have four cameras (poe) and the G4 doorbell (wireless). I run protect with a sata SSD drive on the cloudkey gen2+. Everything just pretty much works. I have not tried to use other brand cameras though. The experience is pretty consistent with other unifi gear. From my wifes perspective she has never complained and weve had it for 2 years now. It easy to navigate and always works.

Only thing id note though is you probably want some kind of SSD for the camera storage. A harddrive is probably better long term but without an SSD the video takes longer to load and scrubbing video can get painful. ie your wife will get annoyed. Itll work with an hdd but its just noticeably less snappy.

This is the guy that wrote Task Manager for Windows back in the day. Hes an old Microsoft Windows developer. So even if he used AI id be interested in seeing what he made.

https://tteck.github.io/Proxmox/ this is a good place to start. Also highly recommend youtube videos lots of good stuff there.

Is the server exposed to the internet at all? ie, Did you open a port on your firewall to allow inbound connections? If not, then nothing should be exposed to the internet and you should have no problem. Proton is also a vpn not a firewall and really doesn’t offer much protection against attacks. It basically just muddies the water on the origin of your Internet traffic.