At this point I am moving 4 little pieces of paper around on top of another
sheet of paper with squares drawn on it.

The floor is about 12'x22'. Footprints for the four things a

Car 13'x6'
Lathe 3 1/2' x 5 1/2'
Mill 3' x 4'
Drill 2'x2'

What sort of space should there be between the various tools so I can do
work without having to remember exactly where I am all the time?

Are there any real advantages to having access to all sides of the lathe -
this asked because right now the bench is by itself in the middle of a floor
and it's kind of nice to be able to walk around it.