Thanks so much for these responses! Yes string shelving would be a great idea and would add lightness to the room while keeping the style. Unfortunately the external wall is also insulated with plasterboard because of damp problems so it would be quite complicated and risky to hang anything on it. I have now bought a Brouer Mobelfabrik rosewood bookcase for the one side . After it is in place, I will have to see whether an additional piece would work for the other side But all these are good ideas as I have another room with an internal wall where primary colours and string shelving would look great Thanks for your advice!

Ok, how deep are the alcoves? are You able to do basic diy? I cut my Billy 10cm to fit into the space. It was worth it. I really like your fireplace surround. It would be really nice to get or install something to compliment it. go for billy/ besta combination. besta 120cm (60+60 combination) cabinet with legs and put a top 132cm to go for wall to wall. Complete with billy/besta wall cabinet above. If someone is able to do some diy you can add some side panels to look built in. Look on the YouTube, there are videos people do it. The on the other side take billy tall cabinets (80cm+80cm) as built in bookcases. go for white cabinets and combination of glass and solid doors. You would be also able to add some cabinet lights . Good luck. Let me know if you need help x

A picture of the space where this office/media unit will be situated would be useful. However the picture Elena has supplied that you like could be achieved with IKEA units (Besta units, Billy bookcases, floating lack shelves etc) If you Google IKEA hacks you'll find loads of examples of where people have done this and then added wood trim to give the effect of a bespoke built in. Depending on your skills and budget you could do all the flat pack assembly and then pay a joiner for the wall hanging and finishing touches.

Do you mean just a shallow cuoboard en suite? The other room that mimics this one had a weird box just stuck in up to the ceiling on the right side and it left an awkward space but also cut into the ceiling. Will see if I have a photo tomorrow to show you what I mean. But that has a shower and it's a tiny room so didn't want to take that much of it up. I might remodel that as well to make it longer 😂 Thought if we made it look almost like freestanding furniture/storage cupboards then someone could use it as a lounge as well in the future (especially if they turn the house back into one) but I don't know. Its not desperate but when we do our current bathroom next to it then I need to decide as it will need plumbing in at the same time. 🤣