Yup, the extensions are annoying, but luckily many are packaged, at least in Debian. I have one to get sane Alt-Tab behaviour, a media player indicator, a weather extension (in the middle of the top bar, next to the clock), one to get a suspend button, and another one to arrange my workspaces in a grid. Of those, only the last one isn't part of the gnome-shell-extension* packages. It's annoying to have to use a "tweak tool" to manage this stuff.