The lack of a 3D grid and a dimensional axis system seems strange to me; the manipulations I'm performing are all about precisely positioning objects in a 3D space, but the only real tool I have for doing this is yanking along a 2D plane - why can't I specify the motion of the object more exactly? I ought to be able to: (a) isolate motion along certain axes or planes (e.g., only move it in the XY plane or the XZ plane, or only along the X axis, etc.) and (b) specify a target point in the grid space before I try to move an object.

The grid obviously exists already, so somehow representing it doesn't seem like it would be a big deal; similarly with constraining motion to certain axes.