My experience with NixOS: Package installation is usually just from the official channel, system options can usually be done with `/etc/nixos/configuration.nix` and home-manager.
Major problems: installing niche proprietary software that you may have to package yourself, and fighting Nix for languages with package manager, e.g. Python, which frequently uses packages not in nixpkgs.
Major problems: installing niche proprietary software that you may have to package yourself, and fighting Nix for languages with package manager, e.g. Python, which frequently uses packages not in nixpkgs.