How lovely to have a fireplace in a dining room. I've always wanted one in a dining room or a kitchen. It is your house & if you want it lighter I would start with a diluted latex off-white paint. Use a terry cloth rag to dip into the paint & blot or dab on the bricks. Just do it by eye. You will know when you have enough on it or to add more. The idea is not to 'paint' it but to lighten the color & have it blend more into the background better.

I would only do this after removing the mantle. Try to get away from so much grey or beige on the walls & furnishings. I love your floors. What are they? Could you find a very narrow light colored sideboard to place between the left wall & your table?

If you are planning on drapes or window coverings at some time go with a sheer white grommet top drapes to help bring in more light to the room. Hang from the ceiling down to the floor. You can buy two tall narrow lamps to place on either side of the sideboard. Add a filigree bowl of lemons & limes to the center of sideboard & go to Great Big Canvas.com to look at their art. Go big & only you can choose your art.

Put a piece of art above the sideboard at about six inches above & get some great decorative metal art to hang above the mantle that you replace. Go to houzz to check on mantle styles before replacing yours. Enjoy your lovely new house

Thank you for commenting! The floors are travertine. Yes, I am definitely adding sheer white curtains - great minds think alike. :) I am deciding whether to put a sideboard where you mentioned, or on the other side not pictured. Great idea about the large piece of art (with pops of color) and the lamps. I really appreciate your thoughts and will update with what I decide.