Some option to go with the same style wood slat for FP.

or just with wood slat built-ins doors

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or both doors, and FP surround.

Are you redoing your floors? I presume that removing the hearth will leave a mark on the floors.

I would get rid of the trim around the windows and the molding on the fireplace and edge of the shelf below the windows. Basically, you want clean plain edges with no trim. Or if you need trim to finish off an edge, it should be rectangular and plain. I would remove the white stripes in the two windows near the fireplace. Celery's wood slat fireplace surround is nice but that may be more than what you want to do at this point. I would remove the TV from above the fireplace and put it on the wall where the two chairs are. Arrange your furniture closer to the center of the room, rather than against the walls -- maybe with the sofa facing the wall with the TV and the two chairs facing the fireplace (or vice-versa). The white beams are very off-putting to me. I would paint them a dark (very dark) brown or brown-black. I don't know if you have exposed beams in the rest of the house, but if you do then they should all be painted the same dark color. You would have to evaluate that before embarking on that change. Ideally, the beams would be stained rather than painted, but since they are already painted, that ship has sailed and you have no choice but to paint them. One of the professional decorators could offer suggestions about furniture; I'm not a pro so I would leave that to them.

What about something like this? Would need new windows/clad beams in wood but other than that shouldn't be too difficult...tile is Fireclay San Gabriel 2x8

You might consider just decorating with MCM decor and not redoing the entire fireplace area. However, if you look at a few of the images below, you'll see how we have helped out clients with some MCM decor.

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Atomic Ranch MCM Main House · More Info

Paint it the same blue as the kitchen, buy an MCM inspired couch, throw down a geometric pattern rug with your colors and find MCM coffee table and chairs. Messing with the shelving and windows that frame that wall is expensive.