A long Art piece with pendent lights above the fireplace and a pottery piece on the right would look good

you need to create some interest by adding a beautiful and substantial mantle and perhaps a stone enhancer to add some life to the stonework. I would also use the space on the right to store wood which would require some work to be done to create an opening to house the wood. Then lastly I recommend decorating the mantle with a great piece of art, or a mirror and some accessories.

If you do pick pendant lights, do be careful to place them so that people walking in the room don't accidentally bump their heads on them!

Ceiling pendants should hang 12-20 inches below an 8-foot ceiling. Add 3 inches for every additional foot of ceiling. There needs to be at least 1 foot of clearance for people walking below the pendant.

You can pick great pendants of any style and price point to complement this space. The angled ceiling isn't going to be a problem. See our selection here to get inspired! http://www.lightsonline.com/pendants/

Plow and Hearth catalog (online) has some nice glass and metal screens. I have one and it totally changed the look of my fireplace. I agree that you should leave the fireplace without a mantle and concentrate on some accessories that express your style.

http://www.wayfair.com/Minuteman-International-Cypher-Wrought-Iron-Fireplace-Screen-VS21-XMM1293.htm

the one I have selected is one of many on this site which I think would look great in your space... take a look at the options and very reasonable prices.

I use this shopping site often for clients & very impressed with quality of products, service....

http://www.plowhearth.com/glass-two-door-fire-screens_p11604_s2011_d4000_c1027.html

I think something like this might look more midcentury/modern than what you currently have.

Thank you both - Garza Concepts and Kelly Designs for your feedback! Very much appreciated!

Garza Concepts - Your idea of adding lighting above the fireplace and the long, substantial piece of art is excellent. I love pottery, so that would be good on the hearth, possibly.

Kelly Designs - Enhancing the mantle is probably our number one priority for the fireplace! It's great you honed in on that, too! What would you do to it? We've considered having a cover made to go over the mantle - like a stained, modern beam-like shelf that would cover the existing mantle and would match the beams we have on the vaulted ceilings (which we're restoring to a darker wood tone). We've also thought about covering the brick with a stone veneer to update the fireplace and give it that roman brick/midcentury look. We have darker hard wood floors throughout the home.

Thank you again! This is the first time I've posted! :)

Kind regards,
Mark

Wouldn't add a mantle. A painting or a piece of metal art and I would add track lights to shine a light on your fireplace. It would really bring your fireplace (and art) to life. You could mount them on the side of the ceiling beam:

see the attached photo for an idea on a modern dark wood mantle

Sharon Charboneau, LightsOnline, Carolins and Handymam - thank you for your excellent ideas! Also, thank you for providing links and photos - these are very inspirational! I'm getting the idea of lighting being key to bringing the fireplace to life - particularly when it's not lit (which is most of the time in Dallas, Texas!) :) You all are awesome! Thanks again!

Good call kellydesigns!!

I would say that the mantle kellydesigns posted is more rustic than modern? Not that it isn't a nice fireplace. But I don't see it as modern. What am I missing?

If you look at the pictures posted by "carolins" & "kellydesigns", I notice one thing right off. The wall colors of those rooms are good for showing off the color of wood. The dark slate/blue walls you have now make it hard to get the contrast you need to make the mantel or beams pop out. As far as the posted picture of a modern mantel. I think it qualifies. The attached picture is what I would call rustic. www.mchandyman.com
Dallas.

I would go with a really interesting metal fire place door then compliment with the hanging pendant lights. Then leave it alone and let the fireplace speak for itself!

Have a vertical, non-flammable wood chest built to the right of the fireplace. It would reduce the massiveness of the brick, add height, and be practical at the same time.