I jumped ship from GNOME 2 to XFCE when GNOME 3 was announced and have ranted about it endlessly, but then I decided to give GNOME 3.14 (Fedora 21) a try.
I still installed Fedora XFCE on all the PCs I care about, and decided my personal laptop was the perfect guinea pig for GNOME because I never do anything with that laptop and wouldn't mind re-formatting it again for XFCE if I turn out not to like Gnome.
After scouring the GNOME Shell extensions I installed a handful that made my desktop somewhat tolerable:
And then I found way too many little papercuts, some worse than others. My brief list:
Settings weren't always respected very well, and some apps would need to be "coerced" into actually looking at their settings. For example, I configured the GNOME Terminal to use a transparent background. It worked when I first set it up, but then it would rarely work after that. If I opened a new terminal, the background would be solid black. Adjusting the transparency setting now had no effect. Sometimes, opening and closing a tab would get GNOME Terminal to actually read its settings and turn transparent. Most of the time though, it didn't, and nothing I could do would get the transparency to come back on. It all depended on the alignment of the stars and when GNOME Terminal damn well feels like it.
Also, I use a left handed mouse, and GNOME Shell completely got confused after a reboot. The task bar and window buttons (maximize, close, etc.) and other Shell components would be right handed, while the actual apps I use would be left handed. So, clicking the scrollbar and links in Firefox would be left-handed (right mouse button is your "left click"), and when I wanted to close out of Firefox, I'd instead get a context menu popup when clicking the "X" button. Ugh!
I wanted to write this blog post from within GNOME but it just wasn't possible. With different parts of my GUI using right-handed buttons and other parts using left-handed ones, I had context menus popping up when I didn't want them and none popping up when I did. After a while I thought to go into the Mouse settings and switch it back; this didn't help, instead, the parts that used to be right-handed switched to left-handed, and vice versa. It was impossible to use. I just had to painstakingly get a screenshot off the laptop and to my desktop and deal with it over there instead.
These things just lead me to believe the GNOME developers only develop for their particular workflows and don't bother testing any features that other mere mortals might like to use. All the GNOME developers are probably right-handed, and they have no idea about the left-handed bugs. All of the GNOME developers don't use transparency in their terminals, evidenced by the fact that the transparency option disappeared from GNOME 3.0 and only just recently has made a comeback (in GNOME 3.12/Fedora 20).
XFCE is going back on this laptop.