Yay, thanks for posting again! I love your contributions on the forums!! For the curtains, I wouldn’t focus on pattern or boldness as much as I would texture. It seems like you have a minimal, yet chic color palette set up, and you want to keep the calm and cool vibe of that going with the windows, without opting for so-minimal-it’s-boring curtains.
I really like these and these from Urban Outfitters, both of which come in neutral colors that fit your palette, yet have a draped or ruffled texture to bring some luxe coziness into play.