My sewing room is in one of our three smaller bedrooms. Sometimes, I think about moving it into the master bedroom and the master into a smaller room. But, we like the master as it is now. My cutting table is a 4 by 6 foot folding table and it sits on bed risers for a comfortable height. It is a few inches away from the wall so fabric can easily drape over the back edge. My sewing table is a 3 by 4 folding table and it is always on sliders so I can easily move it where I want it within the room. I have found that the sliders let me make small adjustments in position while I am sewing. It is so much easier than adjusting the chair.
Your sewing room should be however it works best for you.