I've mentioned how much I like the "Gnome Shell" experience much better than Unity running on Gnome 3.
But even so there were certainly still some annoyances. I've worked around those for a while, manually installing and configuring extensions, but it has proven to be annoying as all get out.
But I just learned about gnome's extension site:
This is currently in alpha, but from here you can install extensions with a single click. Pretty cool. Here are some I really like:
Remove Accessibility "turning on" this extension will turn off the accessibility menu from the top panel
Coverflow Alt+Tab this rectifies the single biggest annoyance of gnome shell - its moronic implementation Alt+Tab windows switching. This is a must have, even though I can't say the coverflow style is my favorite. (here is a more simplified option)
Alternate Status Menu why on earth would you hide the "power off" menu items? It makes no sense to me. This extension makes them always visible in the menu.
Dig around, and I bet you find even more extensions you will find useful!