I've had to move my shop half a dozen times in my life. In the early and later days it was for one person, in the middle for a dozen. Always more of a trade shop than artist studio, but they are close enough. Here are some basic layout things I've learned.
Generally I like to think about how work will naturally flow through the shop and position stations accordingly. In a one room shop I like counters, stations and benches around the perimeter with a large central heavy workbench in the center for mills, presses, vises, hammers, blocks, pounding, etc.
Always have more light than a normal room. You need to see the work better than your customers. Same goes for magnification but that's not a layout issue.
Plan for power early (both draw and outlet number and placement). Same for ventilation, I like an inline fan in the ceiling that has ducts branching around the shop to the kiln hood, plating and soldering stations.
I like the countertops higher than normal since I'm usually standing.
Allow space around the sink for steamer, sonic, magnetic tumbler, plating and an area to layout polished pieces on a towel. Also need storage or shelves for solutions and materials used to wrap up finished pieces for delivery, think assembly line.
It's better to separate casting and polishing if possible. Quattro makes a nice enclosed polishing system to minimize dust in a small space.
I could go on too long , so lastly. Think about each station being like the cockpit of a plane. You want to be able to reach everything you'll need quickly and easily when working at that areas task.
Hope that helps a little and have fun.