It appears your lights would spotlight artwork etc. on the wall. I think I would use some floating shelves on either side of the tv. Maybe one longer one with a shorter above it. It looks if you have a white and pale blue color scheme. I would take the nicknacks off of the table under the tv. Try to use a more uniform look for you picture frames, then put them on the shelves along with artwork hung above the shelves. Bring in some unifying color for the rest of the fabrics and colors of wood.

Can you paint your speaker covers? If so, match your wall color. Mine can be painted and are far less noticeable.

Maybe you need an special touch in this big wall.
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Best regards. Macral design.

@Macral - Those units look great !

The other way you could go would be to cover the speakers with custom-printed grilles i.e. artwork/photos. (I'm really not a fan of the flush in-walls). However, they'd ideally need to be spaced further apart to pull that off.

You could alternatively use some bold artwork as a distraction! http://johnwilsherpaintings.co.uk/index.html

Love the units and the artwork!! Thanks to all for sharing thus far!