Great space! Sofa, lamp and tables are larger and more contemporary - all of your accessories are too petite -rug, art, mirror, etc. Geometric and graphic art, pillows, throws. The metal knot on the stand works. Search houzz contemporary yellow and gray accessories.

I agree your artwork is out of scale for the room. Consider two narrow console tables on either side of the fireplace with large, framed, colorful art mounted above each table. You could also bring in two upholstered ottoman cubes to put in front of the fireplace (or under the consoles, depending on depth available). Find a graphic fabric in blues and golds to bring some life into the space.

Here's some suggestion for your wall you might like......to know more about my Art work and collections please visit my shop on Etsy website -

https://www.etsy.com/shop/PooviArtGallery?ref=pr_shop_more

Check out Z Gallerie web site for inspiration and possible pieces that will compliment your sofas and room. You choose the colors for the room and subjects for the art work that appeal to you. Generally would not suggest a mirror over the fireplace if you can't see yourself or something beautiful being reflected.

http://www.zgallerie.com/c-254-living-room.aspx