Here are a few ideas Marie, I did this for someone a while back. In your case, you can use a vent-free fireplace like in the first picture. Or you can try doing something like this a [Nice Wall Unit [(https://www.houzz.com/photos/custom-designs-and-model-renderings-contemporary-new-york-phvw-vp~46015491)

Maybe a floating console just under the TV once you lower it (or get another similar size or smaller TV and put underneath this one for a gaming system :). With the door opening there, not sure you can or should put anything else on that particular wall. If the console had a shelf, you could add some books: sports or cartography or movie related. How much room on the other walls? Any windows or closets to work around? I've created a man cave of sorts so can give suggestions if you show all walls.

paint that brick! 100% just like this Black. here's a photoshop. painted all the brick black, removed all the stuff from the mantle (you can hang them like a gallery wall elsewhere in the room) gave you a larger leather sofa (look on discount places or craigslist, or even Article.com) simple wood coffee table w/black iron legs (Wayfair) and a few regular chairs. cool, right?? Find yourself a large area rug w/some black in it and use it to cover most of the carpet. down the road you can change the flooring to bamboo if you like. find a cheap area rug for now. (under $100) Look at Cost Plus World market. they have some cool rugs. Keep your mantle as is. remove everything from it, take down everything from the walls, take out all the furnture. Do you like the wood paneling? leave it if you do and paint the other walls some other color. What if you went w/a deep forest green? get yourself a leather pouf pillows like these I'd do a jute rug in a deep charcoal, something like this And if you can find a leather sofa in this color, even better! look how great it all looks w/the black and textures. Find a second-hand dresser and paint it and mount your tv above it other colors for the brick or even the walls paint the brick a deep navy color if you like do you like any of these ideas? I have more fireplace photos

Not a fan of the rugs. You may find it’s easier to make decisions if you first figure out how you want the room to feel and have decided on a colour scheme (there is so much inspiration on line). I could see a textured, layered look, practical/durable rug, patterns, warm colors, black metal/wood tables, fun art with black frames, simple bamboo blinds and good lighting. Choose a room you like and then start to focus on accessories/how room was pulled together.