Ello, I was wondering, is it possible to bias the distance ratio uniquely per point in a voronoi fracture?

Maybe not exactly what you're looking for, but I did something related in the past by creating a rest position, then distorting my geometry by bringing some of the points closer and some further to/from your voronoi points depending on their scale. Then perform the fracture and restore the rest position. This requires sufficient subdivision before your fracture, however.