I can see that a tv flat against the current blue wall may prove awkward to view from the room - but extending the idea of carolins illustration, placing the tv diagonally across the corner would give you more scope. Though you might feel this generates 'dead space' in the corner I think that the sacrifice would be minor in comparison to the improved viewing angle from the room. I would put a back on the corner bridge, painted blue. I also think that blue behind all the shelving would look fine - but why not make it up and stand it in place, then decide on whether you want to paint the other wall?

Thanks Carolina - just looked perfect but they only do white not black ! Typical ! Thank you.

https://www.organized-home.com/posts/steal-this-look-the-clean-white-laundry-room/ This article may be of help... it suggests that the wall storage system is adapted from one of Ikea's kitchen ranges... it may be worth going into a local Ikea and asking one of their designers if something like this would be possible with their products!

Your place is lovely and welcoming. I would suggest putting a large mirror above the sofa facing the garden to reflect back in some light and the lovely garden. Your TV wall looks great (accent wallpaper could be indeed a lovely add on but I wouldn’t hand anything) and I agree with you putting a table between the sofas (round and height of chair arms taking up the full space) with a nice table lamp in the corner would be lovely. People can put their cups and glasses on it. If I might suggest a colour that’s not wood such as red or white it would break up the wood and make everything pop. Great job, really nice 👍