I think it looks great and would be inclined to leave it be, but of the options you've listed I would probably plaster the fireplace and leave the walls brick. Lovely room, btw!

leave it alone-agree with sochi and blubird-and go with art. the brick will provide a great background

There are a lot of older homes where the brick installations are done with a cheap ugly brick and in those cases it makes sense to make a change. In your case however, the bricking is quite pretty so I'd embrace it. I think what is throwing me off is the mantel. It looks too low and because there is so much brick, maybe something a little beefier would help give it a more polished look. I like how the one in this pic would sort of mimic the shape of the opening of your fireplace.

I think it looks really cool as it is!

I like the brick as is. I think what is throwing it all off is the black triptych on the mantle. I would do as suggested earlier - lighter more colorful art.

I'd think about floating wood shelves on either side and hanging a large-scale (antiqued) wall mirror over the FP.

LEAVE IT ALONE. It is lovely.

Gosh Finally, you don't have to yell....it is lovely, but the OP is looking for ideas...I think floating shelves on either side of the FP is kind of a cool idea.

Another vote for leaving it alone. It looks nice and adds personality and warmth

That is very pretty brick, I'd leave it. However, if you do decide to do something(for a change) just make sure it doesn't compromise the brick for future owners or even yourself if you want to go back.

I think it's the black triptych panels. Do you have another piece of art you could try out, or if you added mirror, what would be reflected?

Also, could you put some plants or some larger piece (vase with branches) on the ledge?

Nosoccermom, I was thinking the same thing. Either move those up so they are centered top to bottom. Or, a weird thought, just use 2 of those and rotate sideways and bring up a bit.

I think it's a very pretty brick and would leave it as is. Agreed that something other than the dark art over the mantel would be better. And maybe a larger mantle that wraps around the chimney chase in white to match your trim? I Would not put anything up on the ledge. It is a beautiful room :)

Good brick. I'd leave it.

I love it too. it might be helpful to repeat the color of the brick in accessories. pillows, throw/candles..etc. what you have now is neutral and would be easy to add.

What a beautiful wall! Love it as it is!

I meant the bottom ledge. How wide is it?

"Gosh Finally, you don't have to yell....it is lovely, but the OP is looking for ideas..."

Didn't mean to yell, but her question was "Or should I just leave it alone?"

I think if you paint or resurface the brick you will regret it. Two large square wrought iron pieces would look good on each side of the fireplace. I would keep the mantle very simple perhaps place some stone/concrete sconces with pillar candles. Call me crazy but I think it would look beautiful to do an antique treatment with french blue paint on the mantle. You could do a whitewash on the mantle. What an exquisite room. It is gorgeous as is.

I like Christy's idea of softening up the look of the mantle. Google 'distressed fireplace mantles' for ideas. Some of the lighter colored rough hewn beams are also very nice. It looks like the mantle is a little low to me because it's so close to the arch. I also agree about exchanging the panels above the fireplace. They just look visually heavy in your pretty, light and airy room.

Pretty brick. I'd leave it. Like the idea of beefier mantle and antique mirror over it.

What a stunning room! I love your brick & wouldn't change a bit of it. Would love to see more of your house!

I can't tell from the pic but could you put some freestanding bookshelves on either side? Kind of like this?

Maybe not that modern, but in keeping with that sofa table you have.

Or two lower units and lean tall art or mirrors on them so you don't have to drill into the brick.

That is a lovely room! The disconnect I see is the style and color of the furniture with the style of the brick. I don't know what to suggest in place of the furniture - which is quite nice - but I'm thinking something more earthy.