I am unable to send to arch-dev-public for some reason so i am send my
reply to arch general.
I think the filesystem can be split, the sysuser/tempfile will be in the
independent package. I do believe we seriously need a meta package for
some parts of base. Systemd, Glibc, PAM, Filesystem, Coreutils,
mkinitcpio ,Util linux and linux firmware are obviously need to be moved
to a metapackage. This helps since it makes it easier during major
transitions in the future.
Stuff like editors, bootladers, kernels (efi partions when dual booting
has space for a single kernel), snail are optional and remain as a group.
The meta package takes place of all other package of the base group.