WE got rid of our curtains when we repainted, BEST decision ever and now have plantation shutters, they are awesome, look clean, modern yet as we have a Bluestone villa it so doesn't have to be just modern homes, still looks great with the cornices etc will go any where and look great, I liked the Temple and Karari rugs as they won't date then you can add pops of colour such as teal and navy or yellow and navy or really most colours go with the soft blue/navy it would be whatever your taste is in the pop of colour, red or burgundy....choice is endless really, We did have full window shutters.

I was always wary of colour & turned to Houzz for help when we bought a house with terracotta tiles! (Sometimes you have to let the other half win) I took the advice of a very clever lady here & love the rug she suggested. Don’t be like me, try colour if you think it may work. You can always take it back!

Many thanks for all the helpful suggestions. I was really keen to move the sofa forwards off the window but my husband doesn't like it in this position. I have finally settled on a coffee table nest similar to your suggestion @julie Herbert  Order online so fingers crossed I like it when I see it!! The hunt for a rug continues, that textured one is beautiful do you know where it's from or any ides where I can find one similar

For colour, I would look at something light (unless you have kids or pets!) given there is a already a dark floor, and the dark paint around the windows. Perhaps an off-white or light grey shag, which would fit with the mid-century look. Of course, if you are looking for a darker, moodier vibe, feel free to ignore me :)