The only change to my sewing set-up now would be no stairs! I have made my daughter's old room into my sewing room with a daybed to stack stuff on, I use the trundle underneath to store bat and backing (no mattress!), have a tall shelf for magazines, books and clear boxes of smaller scrapes, plus a glass fronted armoir for more fabric. I have my sewing table on one wall next to a large desk where I can rest large quilts as I sew. And in the middle is an old drafting board that I cut at--wish it was little larger, but love the height with no bending. Across the hall is my son's old room, now the guest room, where I use the queen size bed as my "design wall". I also have bathroom upstairs.
Then in the basement is the long arm with a great window in front of it, the stereo (I have to have music to long arm and usually choose something that reminds me of the quilt), shelfing, both open with some baskets for those small items, and closed for patterns, etc. An old kitchen table where I can lay out stuff, work with customers, or use as the side table if I'm working on the industrial upholstery machine (not often--it's like lifting weights it's so heavy duty!). I also have the dining room table covered with padding to use as an ironing board for quilt backs. And in between is the living space and where my husband usually spends his time writing! Works great--except my knees would like a lift!