You don't need to compile and run with the same jdk version. Dunno why you think this.

It's a good choice. Just avoid installing stuff from the AUR (at least no system packages)

So what is a better paradigm in your opinion?

30 character password + fail2ban after one failed attempt. Why not?

Debian + Flatpak for Gaming (Steam, Heroic Mangohud, etc.)

Create a sudo rule which allows the user to run only this exact command: "sudo docker restart mycontainer"

Ich sehe hier erstmal keinen Widerspruch? Zusammen mit der Waffe müsste man deutsche Soldaten zur Kontrolle hinschicken, und das möchte man nicht.

Don't use startx to start X, use the display manager: systemctl restart lightdm

Why would a package called "masterpdfcreator" overwrite the x conf? I don't think the AUR packages have anything to do with the problem.

It's not rolling, but you will automatically receive cinnamon updates over the mint repository. For gaming and latest software you can use flatpak.

und was ein Leben :D

I'm on Manjaro since 5 years and don't have any lags or "odd discrepancies" with the AUR (AMD setup, xanmod kernel). The general antipathy towards Manjaro on is not justified IMHO.