Whenever we go to Mont St-Michel, we stay intra muros -- inside the walls.  When the island shuts down for the night and all the tourists climb aboard their tour buses and leave for their next stop, the Mount becomes a quiet, restful hideaway from the cares of the world. 

The accomodations will, necessarily, be on the Spartan side;  there isn't much room to devote to 'luxury apartments' here.  The restaurants attached to each of the half-dozen hotels on the rock are all exceptional...  just what you would expect from France.