Yes floor space, for roost space 12-18 inches per bird. Keep 12 inches of space on both sides of the roost so neither beak nor tail are smushed into the wall. 3 nest boxes per coop should be more than adequate as most times they will share anyhow.
The coop should average 4 sqft per bird. The run should average 10 ft per. I have a 16 by 32 coop and my flock is free range. For ease of cleaning I would advise making your coop tall enough for you to stand up in. I also have a smaller coop I use as a grow out coop, as I raise my birds for...