Since you asked I'll dump my nebulous wishes here. Sorry that I don't have very
concrete suggestions and solutions, just things I think could be better.  I
should also state that 99% of my thoughts about Guix are through the filter of
"I want to build a Guix based desktop distribution that can be installed on
library, school, and home computers and Just Work better than Microsoft Windows"

1. Improve guix pull and updating reliability.
Updating guix for me is often like this:
$ guix pull
retrieving git objects....
TLS error in stream blah blah blah
$ guix pull
retrieving git objects..34%......... *dies but doesn't return to the prompt*
ctrl-c
$ guix pull
$ guix upgrade
$ sudo guix system reconfigure...
GUI desktop crashes back to TTY mysteriously.

Basically if guix pull can become as reliable as 'guix pull; guix pull; guix
pull; guix pull;, that would be great.  I think guix has many code paths
pertaining to downloading files where it chooses "Give Up" where "Try 2 or 3
times first" might be better.

Often downloads to source tarballs will download at ~30KiB/s. maybe some
axel-like system where both upstream an mirror urls are used might be good. Also
this may be wrong but from memory I think if the hash is wrong on a source
tarball, it will not bother trying to use the guix ci mirror of it, only if it's
404. So people with --no-substitutes can get completely stuck.

2. 'guix system reconfigure' without instantiating the new system until reboot.
I think the fact that reconfigure changes the whole system while its running is
a bit of a party trick, like pulling the table cloth out without any glasses
falling over.  For a Desktop GNU/Linux it kinda just accidentally works much of
the time. I've always thought I'd prefer the default to simply install the new
configuration in to GRUB and tell the user to reboot or add some flag like
--instatiate-now.


3. CLI consistency, e.g.,
$ guix package => nothing
$ guix system =>
guix system: missing command name
Try 'guix system --help' for more information.

$ guix package --list-generations, but
$ guix system list-generations ???\

Also https://issues.guix.gnu.org/47618


4. Make guix simpler and more performant.

Guix is complex. It has features that make it theoretically superior in many
ways, but in practice hasn't reached the reliability of simpler systems.  Every
aspect of Guix seems to take more time, cpu, ram, hd space than say pacman.
It's a bit beyond my skills to figure out how to actually improve these things
though.

$ guix system foobar

takes 1.5-3.0 seconds on SSD, stats 2374 files, with 345 No such file or
directories in order to determine the command doesn't exist and do nothing.
A fast guix could have 'guix time-machine -- environment --ad-hoc emacs --
emacs' run instantly after its been ran once, and some kind of 'guix run'
command could be added.

5. I think Guix should have some simple system to only update to the latest
commit where behemoths like webkit/chromium already have substitutes available
and that should maybe be the default way to update. It's not a big deal if we
are making people build stuff that only takes 30 seconds and uses minimal
ram. Doesn't need to be perfect. Ricardo made some simple scripts that did stuff
like that in the past.