This is a similar style to a lot of fireplaces in historic nation park lodges. A metal curtain or screen would make it look more finished. Or add a group of small fake logs that look pretty realistic.

I love it. It's beautiful, especially with your wonderful wood paneling. Put some wood in there and have a fire is what to do with it!

The carpet doesn't appear to be doing you any favors. If you plan to redo the flooring I would expand the hearth - it's a bit undersized for the gorgeous stone fireplace.

Can you post more pictures, one of the entire wall and also other the walls so we can see the style in the room in order to make suggestions.

Get a flat screen to put in front of it, and place big pillar candles inside it.

Do you mean it's not working as in it is no longer a working fireplace, or it's "not working" meaning you don't like the way it looks esthetically.

same question as palimpsest. if just aesthetics, paint the back face with fire-resistant black paint and/or get a screen. really, I guess that's my answer either way. and then maybe a nice piece of art above it to extend it visually upward.