To me the step through the nix config is a double edged sword, on one hand, I just put something like boot.plymouth.enable = true and now I got a nice boot screen without me having to think about having to regenerate the initramfs or something. But if something is not exposed through the options, the work effort is big, reading through module definitions, the original config of the program, maybe writing a derivation. Can I do in in home-manager etc. But every step of the way I can be sure I can have a working system a reboot away