Emily, with being a renter, I'd definitely check Pinterest for temporary solutions. I've seen DIYs where you can starch fabric to walls with an iron. Also try temporary wall paper/decals, but I'd test a small area first. Cabinet makers or even yourself would be able to create a flush vanity without attaching it to the wall. Plywood, especially hoop pine, has received a lot of traction. It really gives a clean, organic look that you could have custom cut to fit in the area. You could also use it on the wall – it could be stained, left natural, or painted for a feature. Have a look at EchoPanel. It is a decorative, acoustic pinboard that would add a splash of color/design. If it is above your vanity, you could pin pictures, inspirations, etc.

Can you do anything with shelves on the blank or door walls? Are the cupboards a built in wardrobe, or is there capacity to put your chest of drawers contents either on shelves or in baskets in the cupboards? Is there room for a freestanding hanging rack of some sort if there is no wardrobe hanging option? Pics would help!

"I thought maybe a wall in front of the wardrobe at the bottom creating a walk around wardrobe, but I think then the bed would jut out into the entry space, not sure if this would be an issue other than for looks?" You don't really have the width to do this... being that you want atleast 3m for the bed to sit against imo (3m if bed & bedside tables). leaving only 600 which isn't enough to get around into the robe. Knowing the size of the windows may help with a solution (i.e. if w06 a high window could bed go under?). Also, the room being only 4390 overall means that between the robe & 1200wide sliding door you only have 2.5m approx. As above, move the bedroom entry door to the other side of the ens. and move the ens. door into the hall, but you may still be tight for room. You could move the robe to against the ens. to end with a 3x4.3 approx. room?? Just another option for you to consider.

Colours like in the previous pics, tan leather cushions, white euros, a fab textured throw even a fur throw, black also would look dramatic with your charcoal bedding even mustard would add a stylish look , white, mustard, Black and Tan would all go beautifully with charcoal.