Solid couch would be my choice and don't foret to order patterned pillows for all three pieces. A patterned fabric will become outdated more quickly and updating pillows over the years will keep it modern and allow you to change decor. In regards to other two, I would go with plain fabric for a 2 seater and if you don't need the seating capacity, go with a single patterned chair to bring interest and when tired of it, less expensive to reupholster only one chair. [houzz=];[houzz=]

Here are some photos that may help you. You have the ceiling height to have a nice heavy rod just above the top of you window that could run the ceiling width. That will give you the space to draw curtains back to expose the entire window. I highly suggest that you work with a designer. A good designer has access to literally thousands of fabric choices and will be able to help you in selecting the perfect fabric and design for your room.

I have a few suggestions. Hope these will help. Go for a wooden sofa set. I know many people nowadays tend to go for fabric sofa sets and sectionals, but i fee that wooden sofas never go out of style. Also, you can change the upholstery colour any time if you want a more colourful look or a colourful slip cover (you can get a local uphostery guy to custom stitch one) which can be washed easily. Go for sleek furnitures that are not heavy. You can also add a few accent furniture pieces like an accent chair if the space allows for it. There are couple of things to note when you bring in colour. Choose one primary colour and maximum two secondary colours. See these links to [pep up your space[(https://www.houzz.in/magazine/is-your-living-room-too-brown-here-are-8-ways-to-pep-it-up-stsetivw-vs~101141558) and liven it. After you choose your colours, pick your decor. Add dashes of these colours through cushions, vases, flowers, paintings, figurines, curtains, carpets and other decor pieces. If you have a favourite painting, pick your accent colours from them. Or if you like the colours in a particular cushion covers, the other pieces can be colour matched. Always hang your paintings at eye level. I noticed that your hang your frames quite high up. Place them around 57 - 60 inches from the floor. Hope I could help

I feel partitions are not needed. You already have too much for the space. Adding a partition will shrink the space further. The simplistic solution, you do not wish to discard any furniture would be to paint all the walls in lighter pastles. And use some wall painting frames to highlight certain walls.