If I ever get a sewing room I dont expect to see the walls for the book shelves and stash shelves and design wall and everything else I'd love to have... well maybe Id reserve some space on the wall for a photo of my other half, since it might be the only way I'd see him...
I'd have thought a nice neutral cream or something, so that it doesnt clash with anything you work on, and doesnt play around with the light too much.