Ok, I am going to say it - NO cushions or throws unless you actually use them.
I find all those 'dressing the room' stuff from TV designer shows is rubbish to actually live with.
No radiator covers, they are twee and block the heat.
I think at the moment it is veyr plain. It needs, as PP said, something else, some texture. But whatever you put in, make sure it is something that works in your lifestyle.
So, if you like reading, add a bookcase with maybe a plant or an ornament or two.
If you like pictures, or have some great photos to go up, add some pictures.
if you are a clean line/minimalist and the idea of cushions/pictures and ornaments is an anathema, then add a large rug, and curtains, or colour on the bedding to add a second dimension to the room.
I love the walls, but I would curtains with that colour in in some way, they could even just be the wall colour + white, that would tie it all in, or you could add another colour to the mix and then more pops of that round the room.