It will install all the packages needed to have a default gnome session,
if you want more gnome packages I suggest you to just open up
Spritz and search for
gnome or any gnome app you want.
For example if
gnome-mplayer insterests you, just search for it.
I suggest you to use equo for installing rather than Spritz, since it is more reliable.
"gnome-light" is just a meta-package, so if there are too few applications for your needs, just add the ones
you are interested in
