Well I installed GNOME once my Ubuntu install finished because Unity is ultra gross, and used GNOME classic right off the bat, but it still feels off.Are you talking about dependencies on Gnome 3 in particular, or the GTK tool kit? I don't think anything depends on you running the former, maybe some official applications but probably not even that. Ubuntu doesn't even run a pure Gnome 3 desktop so anything you're seeing there and in the software center is fine at the very least.
I see. Thanks.It's probably never coming back, there might be extensions making it a bit more like you want it if you're willing to look after them - check https://extensions.gnome.org/. Otherwise, XFCE (http://www.xfce.org/) is close to the Gnome 2 experience, a bit different but good and lightweight. A fork of Gnome 2 also exists, MATE (http://mate-desktop.org/). No idea how good it is.
Edit: Oh, also some users who don't like the newer desktop philosophies of Gnome and Ubuntu seem to like Linux Mint (http://linuxmint.com/). Might be worth checking out.
I wish it was just as simple as being able to install GNOME2