I love your sofa and assume you need to use that door next to it.... Agree with everyone that built in shelves on either side of the fireplace would be step 1. Rather than having your tele in front of the window, how about having it in the alcove to the left of the fireplace, but having it swing out so that you can view it in all areas of the room? I would then put the trunk in front of the window and your new armchair where the trunk is. A lampshade that doesn't create a pool of light under it would be better. Something round so it gives diffused light and then a lamp in the corner near the sofa on a little table, or a shelf built into that alcove, would be lovely for ambient lighting. And I think a stove that you can't or won't use would be a waste, there. If you would use one, by all means, put one in. Otherwise, you can get simple, industrial wall brackets for guitars and other instruments. Your guitar would look gorgeous mounted in there on an angle. I'll try and find a pic of what I'm talking about, but they clip into place and then when you want to use them, snap them out again.... pretty and practical!

So, I had a change of thought following everyone's ideas and input - what do you think? The main feature / wow factor of the room is the garden view from the large door. The woodburner / fireplace is secondary. Along the back wall, we shall build a false wall approx 400mm deep, this will house the inset fire (considering children in this and remembering how my poor kitten jumped on the top of the wood burner and burnt his paws last winter). The unit will have shelves, lighting and be an entertainment centre and the TV will be in the back corner (could be hidden with a painting if necessary) and can pivot forward to watch as a family. - Similar to 2nd image. Long narrow shelves - decorative feature. I like this stovax inset fire. TV to the left of inset fire something like this below TV. The inset log burner can have a flue that has 4 x 45 degree angles if necessary to get up the roof and flue at the corner of the building - maybe even bringing the flue nearer to the upstairs window. Framing the large window, I can have lights, floor lamps, pictures etc. I would like to have curtains / voile to frame the window. Then built into the ceiling we could have cinema projector which faces the smaller door and the blind will be a white blackout blind also acting as projector screen for those night time cinema nights with popcorn! Rough mock up a it takes so long to put walls in and to design an entertainment centre, Please note, the furniture in my revit model is very limited but this is the model we have used to design the house at the beginning. Where the red arrow is - this is blackout blind projector screen ceiling mounted Any thoughts?

I would say taking up a chunk of the otherwise useable wall with a radiator really isn't ideal. if you really can't afford to move it, then I would look at how beautiful/low the window is. If it starts low and the room is not super light, I'd be worried about blocking the light. conversely, if its v bright then def dont put TV opposite the window. I would def think about whether this is south/north facing before planning. looks like a lovely room, good luck!!

Thanks for the feedback guys. I have 4/5 days and I am off from work. I also have a friend or two to help. The plan is to: Day one: strip the wallpaper and sand the wood around the room. The wallpaper has been on for around 7 years and under the paper is lining paper. The paper is decent quality but has seen better days. Day two: paint ceiling and start painting the wood. Make a start on the new lining paper. Day three: paint the walls and finish wood. Day four: add some new furnishings and last minute touches. Maybe new sockets and switches and the ceiling light. Add a rug maybe too. Bonus if I can add some shelving in the alcoves etc. The archway leads to some storage space under the stairs. Currently houses a chest freezer. Thanks, I know advice is not enough time but it’s the only time I have when kids are out and stuff can get done.