I went all gnomey on my desktop because of you 3.18 seems actually OK other than it's it's a big fat RAM hog
I'm of the "We've got 8 and 16GB standard in our computers these days. 300MB ain't bother me none" school of thought. Yeah, it's fatter than most Linux DEs, approaching Windows and OSX levels, but the tradeoff is you get a lot for it. If you want or need a light running desktop, you have tons of options for it, but I think Gnome feels more modern, and is actually really user friendly...once you get used to its weirdness.
If I were to convince someone to use Linux, I'd use Gnome 3 to do it.