I went through this process a few years ago, and I’ll tell you that you just can’t plan for everything.
But do put in twice as many outlets as you think you’ll need. I have 2 dedicated circuits for my space with 2 kill switches at the door, and they are both on a GFI (ground fault interrupter, I do gemstone carving and lapidary work also, and water and electricity made me nervous). My overhead lighting is on a separate circuit as I didn’t want my lights going out if I threw a breaker.
I do enameling and lost wax casting, so an overhead vent above my kilns vented outside was a no-brainer. I got lucky and got about 18’ x 2’ x 1.5" soapstone lab countertops from a high school for free for the kiln/casting area. I got another cultured marble countertop from Habitat for Humanity for free, too. My husband and I made the benches that hold the countertops out of bolted together 4"x4"s and 2"x4"s so they’re very sturdy.
I also got lucky on heavy trash day when someone was throwing away a kitchen-worth’s of cabinets. They line one wall.
I wanted vinyl (softer for when I drop things on the floor) but ended up with ceramic tile. Guess what, molten bronze burns ceramic tile almost as easily as it does vinyl. It also cracks and breaks when you drop things on it. I know I’d have more burns if I had vinyl, but the tile looks horrible now, too.
There is never enough room, as your interests will probably continue to expand. DON’T do what I did; put your books somewhere else; they end up occupying valuable space. DO leave yourself an escape path to the doorway and have several fire extinguishers in strategic areas. I do my casting at the furthermost end of the studio with an unimpeded way out.
James Cohen is right, keep polishing away from everything. I actually do my buffing outside, as it is so filth-making.
Lighting is really important, too. I have 2 fluorescent lights overhead, with 2 hanging task lights on surge protectors so I can turn them on when I’m working in those areas. They have the spotlights that you can direct to certain areas. I also have spotlight lamps for other areas. My shop has no windows by choice. I wanted it to be soundproof and didn’t want to make it easy for anyone to break in.
Have fun, it’s exciting to have dedicated space to work in! Let us know how it works out.