"I want to update the tiles with tile decals. " In front of a fireplace? Looks like you use this fireplace, and you expect decals to last exactly how long?

If it were me I would take away the arches and shelving in the niches and slip your 2 glass display cases right into those spaces. would do tile rather than stone in your fireplace surround, but i like your stone. But I wouldn’t touch the wood mantel. your sofa is fun but it could do with a decadent bohemian makeover of fake fur and fun pillows

I think you could easily tone down the orange stones with limewash or another similar product. There are lots of great tutorials online. I’m glad you don’t want to do a solid color, it’ll look so much better staying as natural as possible. Is there any way to do the mantel and keep the arch? It really is pretty and adds a lot of character.

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.