I think that there isn’t any shortcut, you may define a shorter alias and add it to the registry, though.
Yes, this will be fixed in the next release if you switch to use flakes for the installation of your system, alternatively you can set it manually in configuration.nix file using the nix.registry option. But I don’t have a good example for its compilation and may be difficult to get the git revision of nixpkgs out of the copy installed by nix-channel although it should be there, because it’s used to define the version, I think. Maybe someone with more expertise may fill inn this info.
I have switched to use a flake-based system config for years now because I find it simpler to manage.