I simply recreated most of the tweaks and recommendations from here myself, as I'm always a bit skeptical. It cost me a few hours of my life, but now I know what I did and can react better if something doesn't work or broke from restrictions.
I have now completely switched to Linux (Mint) and updated my configuration. I also implemented a Crowdsec firewall in my network. Although it's said that Linux doesn't require antivirus, I still installed Eset Endpoint AntiVirus.