Hello Luis. I very much like your Guix download page mock-ups that make the download pages give clear instructions. They avoid referring to the manual; this is better at least to many users (who currently probably download the Guix tarball before they learn it was useless).
The question of wording is if it would be an improvement to use terms popularized elsewhere. I have opinions, but perhaps I’m wrongly conservative in this regard. Guix is all about packages, therefore it is a package manager. I believe the shell and container and system, home support are still about packages. Despite other package managers not doing it. Also you write in the system download page mock-up, Guix System were a distribution of the GNU operating system. I believe this is wrong; Guix (not Guix System) is a distribution of the GNU operating system. The definition of OS should not be something like Windows, running on top of an IBM Bios or Intel Management Engine. Regards, Florian