HI -- The rug size should be .. room size minus 18 inches around . Or at least so all the furniture front feet sit on the rug . The bigger the rug the bigger the room looks . Look at these for some ideas . Kylebunting.com .... Onekingslane.com.... Urbanbarn.com..... Westelm.com .... and Ikea.com

I could swear I had posted some ideas for you already earlier tonight, but here are some:

http://www.rugs-direct.com/Details/JaipurRugs-Fables-Lacie/120089/192748

http://www.rugs-direct.com/Details/Surya-Watercolor-WAT5003/114274/182611

http://www.rugs-direct.com/Details/Nourison-Gemstone-GEM02/117820/188722

And reiterating with what the previous commenter said: the rug needs to be at least big enough for the front legs of the sofas to sit on.

I'm trying to figure what material your fireplace wall is made of?!

How about this one? And would it be possible to change the chairs and the sofa around? I think the sofa will look better against the wall and the chairs will look better in front of the window.

Have you considered adding a table and lamp between the two chairs? Here are 5 rugs from Overstock:

I like RugKnots brown/copper art approach [cause I like those]. Depends on what's in view from other room / what's there?

Carolins had pattern [in light rug] which drew nice attention -

But how visible are the patterns in the wall stone???

If you really like purple enough...

Or a grey shag...