It'd be incredibly awesome if push/pull (and other modifications) could include snaps when the center of mass (/ principle axes of the moments of inertia) are in specific positions (/orientations).
Simple example: you want to balance a body by placing the center of mass at the origin. Start with a block, cut part of it out on one side, and push/pull the other side so the mass exactly (to machine precision) matches the mass on the cut side to balance it perfectly.
You could also add something to snap when principle axes of moments of inertia align (to each other or global basis, and to snap when two or more become degenerate)