A blended grid of either one shape or the other, no morphing

I am trying to create a facade (student) design that is an either /or type of thing, say either a square or a circle for windows. I do not want to morph the shapes. For example, I would like to keep the top floor 20% squares and 80% circles, and the bottom floor 5% circles and 95% squares. I am also trying to create a random blend/ population between the two shapes as they intermix vertically. I am almost done with the paneling tools course but I cannot seem to find a way to do this. I am not interested in morphing the shapes, but a semi random populating of horizontal rows. I could certainly do this manually in Rhino but this seems like a good reason to use Grasshopper.
Thanks for your time!

this could be a way:


circles_squares.gh (12.5 KB)