Constrained Circles within a Grid

Hi Grasshopper Community, I am trying to create circles of varying diameters from random points within a Grid. 

The problem I am having is I would like the circles to be constrained within their 200mm2 boxes as well as not overlap one another.

The idea in context, is to make light-wells in a suspended slab within the constraints of the 200x200 square slab fabric. (hence the need for no overlapping) 

Am I approaching this problem correctly?

Any advice would be greatly appreciated!

Regards, TM