I set it up once on install, 4 years ago. I have never needed to tweak any settings after that. Even when installing a different distro (config lives in the home directory)

except that extensions are second class citizens at best, on gnome. Some (or all, sometimes) of them will break after an update.

it doesn’t allow changes to stuff that needs root access to change. If you have root access you can do anything, including switching images. It is not more secure. It’s not less either