As the title implies, should I do it? I love Arch so far, and I can fix most issues that pop out. However, I sometimes wish to start fresh without too much hassle, but I get a feeling NixOS isn't as mature as Arch.
Have any of you used both, and if so, what do you miss from Arch? What are you grateful for in NixOS?
NixOS has been around almost as long as Arch (20 vs 21 years)
you can install the Nix package manager on other distros as an intermediate step to start to give you the feel of things – ie. use Arch to manage your system packages and use Nix to manage your user & GUI packages
While I agree it's nice to have access to nixpkgs' packages in other OSs (I've never did this so take the following with a grain of salt), it is my opinion that you're missing out on the biggest features if you don't fully opt for the nix approach.
I wouldn't reduce the nix tools to a package manager. It's a set to interact with the nix language, which primarily is a language to build a system from. You have the biggest advantage when you know that your system only consists of components built from your set of instructions (of course this pulls in a lot of stuff from nixpkgs) because that brings your system closer to reproducibility. It also makes it more consistent.
I am allowed to use Ubuntu or Fedora (I would use the Fedora but they seemed to have fucked it up) at work. I use Arch for personal. This seams like a good way to learn Nix. I am probably never leaving Arch. It's like a member of my family.