If newScope worked with splicing would a convention of having a flake’s package set be a scope instead of a bare attrset work?
.override the scope on an arbitrary pkgs,
overrideScope for overriding within the scope and having it compose within that flake’s outputs,
no collisions with nixpkgs’ global namespace
e: I guess this is just what Nix-pkgset: Cross-compilation aware (flake) package sets is trying to achieve