I like the idea of a "sofa table": When a sofa is floated in a room, place a table of the same height behind it to make it into a functional area and less of a visual roadblock. I like it with chairs--becomes a great spot to watch TV while doing work.
Dining Room Arranging Problem: Oversize space, multiuse space. Solution: Opt for a table that preserves open space for other uses (for example, don’t buy a huge table with seating for 20 when you’ll only ever need seating for 12). Add storage that will accommodate all the activities that take place in the room. When choosing chairs, select models that can also easily be brought up to the table for extra dining seating. Anchor the secondary seating areas with lamps and occasional tables.