With such a large project I would assume you have an Architect and possibly an interior designer on board--if not you should.
As for the fireplace the bottom right and left "side legs" are to thin. They should be the same width as the side dimensions above. Also I do not see any lighting (recessed) in the soffit above and in front of the fireplace.
PyramidDG.com

You are right! Didn't notice that before as it was kind of an afterthought. We hired an architect for the design of the house, but working with a different GC on the build. Now on a shoe-string budget, so don't have an interior designer; hence, I signed up with houzz.for inspiration and help. :) Any suggestions?

Good old concrete. Use the countertop mix, cantilevered hearth and surround

Funny...@groveraxle, when I first saw the fireplace I was thinking riveted stainless steel.

@groveraxleOMG! Thx. :) Would have never thought about that. Luv the 2nd, 3rd and 4th pix (especially since it's tile I think & less costly?). Saw the same tile for guest bath but looks great for fireplace. Do you think it'll be too much to have that on both areas or will it work?

Eva, I would put the steel only on the fireplace. It should stand alone, IMO.

Even on your "shoestring budget" you should consider hiring a designer, maybe by the hour--there are so many issues--tile corners, mitered or butted, tile layout, offset courses,stack bond, etc, etc. plus recessed lightingabove fireplace is a must.
PyramidDG.com

Have you considered using a white or cream stone veneer? The finished look is very sleek, a bit modern and would fit with the style of fireplace. It is also easy to install and less cost that some tiles and real stones.

The stone that comes to mind is this stone, which in the picture is a wine cellar, but the stone style feels like it would look excellent with your fireplace.

Beautiful Contemporary! What about some brushed stainless?

ErthCOVERINGS Silver Fox Strips would be perfect for this. Available in two sizes, strips and large strips. The stone matches the exterior of the home in its colour, but the style is more modern and clean. www.erthcoverings.com available in 6 colours!

we did this...customers love it

Thought you might want to repeat the vertical screen elements from the outside at the staircase as a strategy [houzz=]

Takes care of "rails" and fall protection but allows the drama of the architecture to come through. Cable rails are neat too - but this is another option that handles two levels well.

I would consider echoing the stucco reglet approach with natural rectangular stone tile flat and modern could be amazing. That coupled with stainless could be neat . . .is the open base meant to hold wood or is it left open because a quartz seat wall will be anchored there?

I would do the entire firepl with a glass tile. I like the silver iredenced Morsic look. In that opening at bottom fill with cut fire wood. In fire opening use white rock for a effect called fire and Ice. Most firepl stores sell, what you need. It's a gas pipe running across and then fill with rock. Has to be made for fireplaces. you don't need a screen. Since you have one keep it open. Paint other walls a metallic gray. Would look great with your stair case.

If you want a flashy, rich, brilliant red color I would use a glass product from Emser Tile. It is from their Vista Glass series, color is Pitau. Linear mosaic or 3 x 6. The undertone is blue which gives this color such a rich look.

You were mentioning you wanted some color..if you go that route, your decor will always have to coordinate, as well as any buyers when the times comes. Large glass tiles laid vertically may be an option if you are going with color. Personally I would go with copper (picture below's link references these can be bought at Home Deptot at $185/slab). Then your cable railing could be in copper as well. Your cobalt or red could be in your art or rugs and the wall beside the fireplace on the right. [houzz=]; [houzz=]