What a fun project! Do think about where you'd like to put your machines, and do you need cut-outs in the top of the cabinet/table-? Where will your cutting area be? Where will you iron? Do you need room for plastic storage tubs as well? Do you need some cabinets that have roll-out shelves? Do you need lots of drawers?
Also, what kind of flooring will you have? What about overhead lighting? Daylight bulbs?
Just a few things to think about~~ v