Just a note, we have fireplace screens on the way. Please ignore the taped boxes to keep puppy from entering the fireplace.

Perfect spot for a buffet.

@cpartist

Thank you for the suggestion! Do you think it would need to be the same height as the wall where the cut-out is?

Can you post more photos of the room showing all walls and your table. You mention perhaps you'd get a larger table but unfortunately not possible to suggest something from the single picture you've posted but your puppy seems to be really cute!

Also, what is your colour scheme in the adjoining living room since the dining room open onto it?

I agree with cpartist. A buffet that fits under the opening. Check Wayfair.

Perhaps simply adding some white shelves to the opening would divide the two room while still leaving any light come through. As on the sketch, moulding can be added below or you can also place a buffet below the opening.

And here's the look with a buffet, easily reupholstered chair seats, and table decor.

I suggest you wait a bit to see what your actual needs are. I am a firm believer that not all spaces need to be filled up!

I do like the idea of a buffet, but wait until you've been in the house a while. You may want something with storage, as lisedv shows, or you may want something more open, like a sofa table, with the dog bed underneath. Living in the house a while will give you a better idea of what works best for you (and maybe having nothing there at all is the best).