(help) weighted point distribution

What I am trying to do: feed the 3d voronoi node with points that achieve tighter densities in defined parts of the bounding box.

initially I tried doing this by moving a populate 3d point cloud to attracters but I am having trouble controlling the density in a constant manner. 

The image sampler looks like the next best option by creating a "heat map" and letting that control the point distributions but I cannot wrap my head around getting this to be random enough looking and translated into 3d space.

I have attached a photo of where I am at in the end result in order to give you a better understanding of the context.