Mate desktop has been fairly stable (the default green tinted icon set is gross but fixable). I switched to it after Ubuntu long term support, and Debian on my other computer dropped gnome 2. Just didn't like gnome 3 or unity. Cinnamon was okay but at the time was still coupled to the brain dead ideas the gnome team had been perusing at the time. I haven't checked it out recently enough to know if it had improved.