Try moving the ottoman to the far right, line it up with the right edge of the shelf. Then place the two speakers side by side lining up with the left side of the shelf. Might need to move the TV to the right about 6 - 8", or try moving the speakers to the left of the shelf. This will also leave some nice large spaces to display larger pieces of art which will help anchor the display. Your three pictures on the left look amazing. Try arranging the vases in two groups, one group of two and one group of three. Also the components on the ottoman, try laying the three side by side. If one is shorter than the others stick a book under it that is about the same size, it will give a smoother look. Flash, how about ordering 6" hairpin legs for the ottoman, move TV to the far right and install floating shelves to the left of the TV for the components. It's like a puzzle, move it all around and have fun.

I am thinking that you should not put a shelf above the TV at all. I would recommend that you get a longer console for under the TV and let that be your décor for the space.

If you are looking for a clean, modern look, then why do you have random decorative shelf directly above your tv? By decorating around your tv, you are essentially drawing attention to something that is not considered beautiful by most people. I also don't see how you can focus on the tv, when your eye constantly gets drawn to random objects above it.

If you must fill the space, add a floor plant to one side and a bookshelf on the other. Think of the tv wall as just that, and not something you have to decorate from H to T. Then again, it's your space. Do what makes you happy.