To make a shed usable you will probably have to invest a decent amount of money. I would decide what I have to spend and see how I could make it work in the house. A foldable 6 ft table (Sam's and similar stores have them) can be used for significant cutting, ironing, sandwiching etc. and stored when your're done. There are great sewing cabinets with storage (start looking on Craigs List etc and post what you're looking for also. Some great storage options and Ikea is a great spot to shop or for inspiration. There are many good idea books and lots of help in the organizational area here. Maybe start by listing your needs to help you focus as you're gathering ideas. Excited to see what you come up with!