Here's another picture

You could do a gallery wall of pictures above the mantle. Keep all the frames the same size and color though. The art should have a similar theme too. For example the botanical art shown below.

Here's some more photos, we currently have carpet but we will be installing the hardwood seen here and the walls will be a grey/beige colour.

what you could try is placing a starburst mirror in the center and two vases on each side of the mantle that are tall and filled with beautiful flowers or vase decor :).

The thing is, you don't have a big bulky fireplace surround/ mantle. So you can't put something up that is huge to accommodate the ceilings because you will dwarf the fireplace. Focus on good design over the mantle that fits the scale of the FP and it will look wonderful. Some people believe that you don't decorate for any wall over 8 feet anyway.

The extra photos are helpful. You could create a beautiful wall at that end of your living room by extending mantle-height wood shelves--stained the same as the mantle--on either side of the fireplace and place your TV on top. A starburst mirror works beautifully with that idea as Carisa suggested.

This wall is crying out for built-ins, at least a new mantle. I got mine at mantlesdirect.com. You need something bulkier.