I use NixOS on a day to day basis, and have encouraged others to do so - and I completely agree with the documentation issues described here. I’ll also note that using Nixpkgs/NixOS will practically require you to actively maintain at least some portion of Nixpkgs to keep it up to date and functional for your specific use case. I think that’s where a lot of the configuration mess comes from - NixOS modules have tended to be created to meet a specific user’s need, rather than meet some holistic design goal.