Maybe I'll get in with this first- art work is hung too high and to far apart.The arm chair looks too squashed in next to the love seat.I would take one of them out. You need an injection of color or pattern as at the moment its all solid tans and dark browns.
I would remove the art work as it does nothing for your space, choose something brighter, introduce a new colour like lime green. Also you could echo the new colour in the rug.
And new curtains to tie it all together.
Have fun and good luck.

Agree with asquithoatley.
Can the loveseat be moved to the other side of the sofa to form an L? Some pictures from the sliding doors looking in would help a lot.

I have attached a third pic