Art IMO is a better choice, but maybe something a bit bigger than you have hung on the wall.

I have made some changes to your room.

That rug is too small and too dark for that table.

Thank you so much love the idea

The golden frame seems a nice complement with consoles edges... ? I don't post this because it goes with the rug, cause it doesn't. Seems to me that the ochre gold in the rug could be considered similar to the gold finishes, but to me it 'drags it down' -- and doesn't go with the grey base/ gray console, "sorry."

Designart Rain Abstract Panel Modern Framed Canvas Art, Gold, 40x30 · More Info

With room's grey, gold, white -- possibly a simple piece would let the rug's pattern "show" more. And do you need lamp[s] as Beverly showed?

"Transition" CF Print, 30"x30" · More Info

Mercury Glass Candlestick Lamp In Gold711/S2 · More Info

Maybe these bubbles would contrast well with angles in the light?

"Crashing Down" by Amy Genser Canvas Wall Art · More Info

Nothing wrong with all 'cool temperature' for sleek --

"Cerulean waters" Canvas Art, 36"x24" · More Info

This one with the chairs

Says these are 37" high? meant for consoles?

Mercury Glass Candlestick Lamp In Gold711/S2 · More Info

I agree that the rug is much too small as well as dark. The tones are taking away from the distinct table base and the coordinating chair legs. As an admitted minimalist, I'd have no rug there or one that's the same color as the floor but textural. The floors are beautiful. Given the many hard reflective surfaces, I think a mirror would be too much and would prefer a textural art piece. The height can't be greater than what's there now due to the vent. Although I really like the candlestick lamps below, it may look cluttered due to the glass cabinet close to the sideboard.

The glass cabinet does not fit in your space. It makes it look cluttered. I know they showed it in the showroom, but that was for a shop display to sell you products!

You need a bigger rug. I would look for something 3 ft wider and longer.

The chairs look cramped at the table. I would remove one on either side. Keep them in a spare bedroom for when you need to use them.

I was going to put a mirror in my dining room because I saw a photo on Houzz that I loved for inspiration. But then I read one of the postings on this forum where someone said she didn't want to watch herself chew while eating in her dining room so she wouldn't put a mirror there. This made sense to me so I bought art instead.

The architecture/quality finishes of your home are so elegant and beautiful!! While you only asked about decor above the sideboard, there are some easy edits that would let it shine. Lose the rug…floor is beautiful, smooth, and easy for the the chairs to slide. Find another spot for the side cabinet…it’s crowding the space. The crystal/marble buffet lamps that Beverly suggested are perfect! Turn off the ceiling alcove lighting. Invest in a piece of real art such as an original painting that you love.

The store showed mirror, etc. with items available for sale. I hope you don't buy another metal or hard surface, as was well said by others.

I think chairs have quilted diamond pattern. Without rug, or with a simple solid heathered type, the texture of chairs will "show."