Beautiful open living room. I'm naturally a sucker for plants so I would suggest something interesting like a dwarf avocado tree to add some extra dimension, color and texture.

There is already a plant at one end of the couch so I would rather see some art work on the walls. You could so shelves if you wanted to but I like your idea of artwork instead. I see texture in the room with the weave of the basket, the metal of the coffee table and the smoothness of the leather so perhaps introducing some colour into your room? It doesn't have to be in your face colour but perhaps a favourite subject matter that would add some further interest.

I like art to be personal so perhaps a print of somewhere you've travelled or a place in your hometown or even framed sheet music of your favorite songs?

One of my favorite inspiration pics...

An original pastel might look good on that wall that gets a lot of light.

How about moving that plant around to the wall and putting a picture next to it but a little higher. If the plants too short, get some kind of stand but not too tall. Then you can put an end table at the end of the sofa. Just a thought.