You can't beat having a bedroom downstairs for whatever purpose you choose. All my bedrooms are upstairs and it's great for leaving your mess behind for days but very inconvenient if you have to be cooking downstairs or doing other projects. When my mother was dying of cancer we had to turn our living room into a hospice room---we really missed having a downstairs bedroom. You can always put a rollaway bed or sofa bed in your sewing room for a guest.