Agree with ^^.
Even though I love brick, there is too much going on here. Choose a feature wall to stay brick, and plaster over the rest.

Leave the fireplace brickwork and plaster the surrounding walls. Paint the door and fireplace mantels the same colour as the timber ceiling beams. I would consider swapping the gas fireplace out for something a little more modern as part of your update. Not sure what the timber cabinet is but I would consider taking that and the giant timber beam off the fireplace wall and add a piece of art a mirror or a TV.

I agree plaster all walls, leaving only the fireplace brick, remove the timber cabinet & beam off the fireplace wall. Update the fireplace e.g. Put in a ethanol fireplace and perhaps feature tile surround and mantle. Place a large over mantle mirror or large painting above the fireplace. Install built in storage cabinets with mixture of solid and glass doors on the full length of the wall on either side of the fireplace. Incorporate your TV maybe a cocktail cabinet etc into the built in cupboards. Switch the lounge around so that the fireplace becomes the focal point of the room. Add a large area rug to define the lounge area. Add a large coffee table and display on it some beautiful and interesting objects/books/flowers/candles etc. Add at least two sofa chairs with a side table between again put decorative and or useful items selectively on the tables. Add lamps for mood lighting, a couple of ottomans in front of the fire for additional seating without obstructing the view of the fire. Google Candice Olsen Devine Design for inspiration on the built ins/fireplace and how to work with the support pole in the middle of the room.

As mentioned above, the brick walls are lovely, but there is just too much going on with the tiles on the floor. I would consider rendering or bagging the bricks, so you still see a bit of the texture (no swirls though!) Reposition the mantelpiece to a lower position, not sure what the timber is above the fireplace, but it would be much cleaner if it could go. Consider some floating shelves on the wall to replace the timber storage unit that is there. You need to play with the position of the sofa in relation to the post and maybe paint the post in a dark colour so your eye is not drawn to it. Definately a large area rug for the sofa and a nice large coffee table.

Keep the bricks on the fireplace wall...it's good that you've painted the ceilings and beams...now keep going...plaster the test of the walls and paint cream / white...move the piano from that corner and put in built -in shelving with crown molding etc and move or paint the book case and place it on other side of the fire place and extend it to create more built-in storage...get rid of vertical blinds...they have no place in this great room....turn the sectional sofa around to face the fireplace and make the built -in to accommodate the TV...place a cream/white rug under sofa with a black diamond pattern on it and put up matching cream / white fairly thick curtains on black or brown rods with fairly large finials then put up bamboo blinds under neath them...paint the door black and keep the trunk as coffee table and place a grey throw and cream cushions on the sofa with grey accent patterns on them like a cross ...then if the budget allows...buy extra seating like a wing chair to place to the left of fireplace...if the brickwork is still too much, white wash some of the bricks and all of the mortar for that industrial touch

Would you consider leaving the back brick untouched but streamline it ? Remove the mantle etc, put big built in book shelves either side of the chimney breast so you can remove any other wall furniture. It looks too busy because the floor & walls are all textured. How would you feel about very simple plastering on all the other walls, painting all the ceiling white, pale sheer view blind & a very large luxurious rug to tone down the floor. Good luck, it's a lovely space to work with.

Agree with most comments and have fireplace as a focal point but remove timber insert above and try and match bricks if possible if you are having a working fireplace. We managed ours by secondhand ones and they match as we had to extend the hearth and found matching bricks as original fireplace was made too small for area and had burnt out. Too much brickwork/timber absorbs light. I have had part of our lounge room plastered as part of room was a log cabin look. The walls are now painted Taubmans hayloft over the plasterboard. It works . If you require a fire and have access to plenty of free wood then fine. If it is an efficient Clean air fireplace, which I think from the photo it is similar to the one we have, get it checked out and chimney cleaned and you can still use for heating. You would need a hearth as well depending on heat output as a building regulation. Ethanol burners are only for looks and are not practical. If you consider this I would not recommend cream rugs as you do get dust. That is the price you pay of having fires. Also a stunning large antique copper pot for holding fire wood would add some warmth to room. If it is gas heating there are some wonderful updated sleek ones now. I would try not to have lounge along window. If budget allows double glazing on large window. Good luck with your project.

Update, I have painted the ceiling all white and done solid plastering on some walls, I was thinking of doing a concrete look finish on the fireplace and getting rid of the timber insert and leaving the walls each side of the fireplace red brick, what do you's think??

Finish your solid plastering on each side of the fireplace to complete the room. and try and match up brick as the chimney is a focal point in the room. I assume you are gong to use this as a working fireplace. If you cannot match brick I would consider rendering the chimney. Keep it simple. Too many finishes compete with each other from a design point of view.
Thankyou for considering my opinion.

Hi Guys , you have probably already done this room already.. But I would have tv and Fireplace sharing the same wall and move the tv if possible to take advantage of the fire on those cold days, would be nice to see tv and wood heater from the the couch area. I understand that it looks like it was an open fire and you have had to box in the flue from the wood heater, so it looks a little nicer - unless there is an option to see part of the flue (like you see on escape to the country tv show' to give character. Otherwise , I would consider bricking up the gap and keep the mantle as its quite nice and render over the fireplace area, then choose if you want to keep the walls either side of fireplace with exposed brick walls but put in 'if you can afford or like - timber open backed booked cases into the space either side of the fireplace. then if you do not like the floor tiles and cannot replace immedately, go for a big cheap dark grey rug to match couch - will update the inside of the house while you decide on flooring alternative and look much more cosy. Just my thoughts, room has good structure - shame that you cannot see the fire from the tv- guess you need to decide if you want to feature the fireplace or cover it up and make focal point of the room where the tv is instead- this will guide you in either plasstering over whole walls - or keeping some walls as they are. cheers.