Come over to the NixOS side…
As an Arch user, you are probably familiar with reinstalling multiple times (an absolute pain in the neck unless you use archinstall) , and having to run long sequences of commands and edit dozens of configuration files in several configuration languages. How do I know? I was also once an Arch user.
But as a NixOS user, you will be able to do anything (well, almost everything) with almost no commands and (at minimum), one configuration file (/etc/nixos/configuration.nix) in one language (Nix), and a reproducible system in which you can provision as many identical systems as you want, and synchronise them to a Git repository and (while putting your secrets in a seperate .gitignore’d file), publish your configurations publicly for other NixOS users to use and fork.
Each time you reboot, you can set up your system to purge all but the vital directories (/boot/ and /nix are the only ones needed to boot) and your precious work and files. By Cleansing Your System With Fire™, you can instantly remove all decay and gunk that has built up in your system and make sure everything works exactly as you intended in your configurations, nothing more or less.
You can install almost any program you would ever need with Nixpkgs, the biggest package repository of all time, period. Just look at the top right corner:
And if you still want more (*gasp*), there are still the third-party flakes that some nix-related projects package themselves in.
And if you still want more, there are still the Nix User Repositories to look through…
NixOS doesn’t provide enough configuration options? You can install third-party configuration systems that fit perfectly into a NixOS system. You want to manage your home environment? Home Manager to the rescue! You want to configure Neovim more powerfully? Use NixVim! You want something else, but nobody else made it? You can make it DIY and share it with everybody else!
And I could go on, but I think that you get the idea! 