I'd say coral might be a bit too light as actually most of the colours in your room are already quite light. What you need is a deeper colour to bring the room together. I agree with ben moore currant red is a lovely colour to go with or even a darker red. You can either stick with your rug or change the rug for either a darker blue or a darker red. From the rug the cushions on your sofas should match. You should have 4 cushions on both sofas, this adds for a contemporary feels. 2 very large cushions (larger than the brown ones you currently have) and then 2 much smaller cushions (similar size to the silver blue ones you have) I'd say stick with the silver blue cushions you already have but then have the bigger cushions match the rug in either a deep red or deep blue, or if you won't replace the rug matching a new coffee table, side table or vase. The 4 cushions will not only add a pop of colour but also make your sofas look more expensive, bigger and add style. To continue this colour theme, the wall next to the window 3rd photo is screaming for a big canvas with those colours. The cheapest thing is to buy a super large canvas yourself and then have a play with those exact colours. Below the canvas I'd add a console table (please see attached pic) where you can put a photo frame, a beautiful modern lamp or a vase with flowers or an orchid. The pop of the red against the blues in the canvas will only lift the room as will the lamp/vase on the console table. If you decide against a coffee table, side tables either side of the sofa work just as well. (see pictures)