I propose adding the simple package speedrect to ELPA.  Speedrect is a modal interface that comes alive when rectangle-mark-mode is active.  It provides easy access to enhanced rectangle functionality.  Beyond all the normal (and a few hidden) rectangle functions, some additional speedrect capabilities of note include:

- auto-restarting (so you can easily chain multiple rectangle actions)

- autosave and restore of the last rectangle

- rectangular text wrapping

- robust in tegration with calc

- quick placement of multiple-cursors