Some items, you wish would not fall. (Looking at all the Anvils, Sand, and Gravel in the world). It would be nice to have a flag to prevent them from obeying gravity. A gravity flag. Upon say /res set Gravity false, any blocks on your residence will not be affected by gravity. Is it possible? I do not know.
Also a flag that is for player gravity too. But that would be crazy if you had players just floating around. The idea is great though!