Well, let's see. A sewing machine in a cabinet or desk, an adjustable ironing board to the right which could be slipped in behind the SM for quilting, a cutting table of some sort, and a simple design wall. Some natural sunlight and supplemental light for sewing (but maybe your eyes are better than mine....). You could put some shelves or a tall dresser in the closet for material and supplies. A source of music and a lounge chair would be nice but definitely no telephone!
That should do it. How does that sound to you?
PS Just about all of these can be bought second hand or with coupons to keep the price down.