First of all, I think your room is really very lovely! The ceilings are great, the wood floors are gorgeous, and honestly, I like the wood built ins. I may be biased since I like stained wood in general and I think it can bring a lot of warmth to a room. That said, I can also understand why you might not. Just throwing out some ideas, I do agree with @Lyn Nielson that the mirrors on the built ins are not ideal and I think it would be a vast improvement to cover or remove them. One option might be to remove the entire top portion of the built in and keep the low cabinets. Or keep the upper part, but remove or cover the mirrors. You don't even have to put the glass shelves back! You could put equal sized large art in either of them, or maybe a TV on one side (if you need one) and art in the other. Like @Patricia Colwell I'm not a big fan of small family photos or decorative doo-dads on small shelves. I'd rather see fewer larger pieces. If you do opt to undertake the whole effort, you could certainly paint out the built ins. (Makes me a little sad, but this is your home not mine.) You could also remove the stone and redo the mantle and surround to painted wood. I do think your inspiration is lovely. One thing to consider is that your fireplace chimney is substantially narrower in relation to the cabinets than your inspiration. With the size of the insert edge, you may not be able to do the vertical legs (not sure if that's the right word) of the mantle plus the trimwork plus the tile or painted brick. Also, just a reminder that even if your home was built as late as the 1990s, popcorn ceilings can contain asbestos (from previously manufactured materials). So make sure to get it tested before you begin demo! It's not worth lung cancer for you and your family to proceed without testing. I say this as someone who had popcorn containing asbestos in my previous home.

@Brittany Kruse I don't think your floor and stone facing are awful at all! I have learned though, that many people are less comfortable with pattern than I am. I have learned that pattern needs some effort to combine and also some plain surfaces to help it fit in. To show you I am comfortable with a different look, I will post a picture of my new main floor bathroom. It is still in progress though. See all the pattern in the floor and walls? Some people are uncomfortable with that much pattern and have said so.  I still vote to take the stone to the ceiling. I think that looks sort of natural, because many fireplaces do. And choosing the right mantle will be important. But if you want to go only to the height of the mantle, that's fine too. I wouldn't make the mantle too busy and certainly wouldn't try to hide the stone with objects. There's nothing wrong with it. Decorating the room around it and that fascinating floor will be fun!

As a temporary thing, I’d just have one thing, solid, centered. Because, there’s this triangle upper shape made by the upper woodwork; the soffit extends past the mantle anyway. Small multiple things just look messy. I like the shape of the metal object because it does have that shape. I’d prefer it darker to pick up the stone more. An almost actual triangle or fat obelisk. But I’d not want you to go out and buy just stuff, or obsess about it. To start, just remove the end objects. Another thing you could try, is a single small art painting, just big enough to be between mantel and soffit and a bit wider, some kind of high- contrast abstract, also centered. You could experiment with using just a piece of paper or poster board.

The fireplace has already been white washed and looks nice. Solid color paint doesnt look nearly as nice as the white wash you already have. The mantle appears to be black, and you seem to have other black accessories. I would leave that also.