So, a long and thin room! Some tips for making it appear wider is to paint the two short walls a dark colour to create an illusion of width! Horizontal stripes can also help, whether it's on the carpet or curtains/blinds. Lighter floor surfaces will help make it appear wider too. Hope this helps! Good luck

Hi Jonathan Thanks for your idea, yes in fact that is what we were initially thinking of doing. But now we are thinking if we shouldn't do a walk in wardrobe at all, so that we open up the space more.

Don’t have dimensions but the en suite looks larger than it needs to be. I would move the wall between bedroom and en suite back a few feet then you could have wardrobe storage space along the bedroom side of the new stud wall. As building a new stud wall you could have a pocket door and I would put the bed and bedside tables as in the diagram above facing the window. In the ensuite I would make the shower as wide as possible stretching between the new stud wall and the exterior window wall and put the toilet and basin side-by-side along the window wall

It seems to be showing up for me so that's strange, I've added it in the comments also, can you see it?