WOW!!...you sound like my brother, he is an electrical engineer and wants to know all those types of things. He shows up with a meter and tells me if I have enough lumens...sheesh
But to answer your question I have 1-1/2 watts per square foot of floor space in my main room in the basement. That is plenty of light without being too much. The problem with florescent lights is that you can't dim them. So you may want to put some recessed incandescent fixtures on the perimeter of the room for times when you want less light. Put them on a seperate switch of course.