I would recommend drapes. A nice black drapery rod, hung a bit high that extends 14-18" or so on either side of the windows. I often use this one from Antique Drapery Rod Co: https://www.antiquedraperyrod.com/5-8-hotel-artiste-radius-rod-3-1-4-return/ Hang white, lined linen drapery, maybe with a nice wide tape down the lead edge. IMO a collage grid will look busy in this space. Good luck!

@ Ashleigh Rader Homes thanks for the comment! I wasn’t sure if curtains would work since the couch is basically right up against the wall. That would look great though!

@ jck910 I hadn’t thought about curtains since the couch is really close to the wall. Didn’t know if it would look right or not.

Ahh I didn't realize the sofa is against the wall. It's hard to see in the photo, so that is helpful. Can you post a couple other photos of the space? If you can float the sofa off the wall 8" that would work! If not possible to float it (or if you prefer it against the wall), I'd recommend a pair of prints on the right (stacked one above the other) and something 3-d on the left. Minted has pairs of prints you could check out: https://www.minted.com/lp/fine-art-pairs The Sacred Beginnings ones would look really pretty in your space. And then maybe a cool basket in a light neutral color hung on the wall on the left side - 16 or 18" diameter maybe.https://www.etsy.com/listing/724200003/binga-baskets-african-wall-basket-wall?ref=shop_home_feat_1&pro=1 Just ideas - balanced but not too matchy and not too busy. Hope this helps!

Use a picture ledge instead. This will be easier and you can change out pics without destroying your walls.