Perhaps a large round table might mean a rug is not at all necessary. It could be a metal tray table, or carved wood like Rebecca Mitchell Interiors illustrates. Ideas also to consider, using multiple tables can be found at http://www.houzz.com/multiple-coffee-tables. I also agree with comments above that some color is needed on the walls. You could then hang round mirrors, or an unusual curved shape like RMI shows above.

@BeverlyFLADeziner: No, I'm not assuming the back has a finish. If you are referring to the cable being visible, or the approach to route it under the sofa would not work, there are two options: Align the table so that the "backless" back is up against the side of the sofa. So, flip it 90deg compared to the image of a sample sofa and this table posted earlier. The cable can be stuck along the curved edge of the table on the back, so that it is not visible. This way, it gets down to the floor along a surface that people cannot see as opposed to dangling through the hollow portion of the table.

Pendants seem like a better geometric fit.

Your setting is good but could be better.the centre table is a misfit.you can use 2 level rectangular table either white poly paint one level and the other level glass or black paint or poly paint.keep the length of the table after leaving approx 16 to 18"on either side.the width can be20-22 " and ht 16".the cushions can be change to black and white design,with a dash of red.a nice rug with grey,black and white geometric design will enhance the effect.brown does not go well with white.i hope this should solve your problem.once you make this change.you eye will pick up the other flaws.