Random nesting of random rectangles

Hello everybody, here is a randomness problem again.

Pattern generation is easy with grasshopper, but when it comes to random sized rectangles, well, things get tricky. 

I managed to randomly populate a 2d space with random rectangles, but what I need now is to somehow stack them together. I tried RhinoNest, but it creates a very smart and patterned nesting (large objects first, then smaller), Then I looked at Kangaroo to try and let the rectangles gravitate to one another, but so far I found only how to do this with circles. Not sure if Packrat is what I need, because I'm working with 2d shapes and making them 3d just to pack feels a bit like complicating things, but if there is not way around maybe it's the way???

At this point I've been working on a problem for so long I don't see obvious solutions for the problem, please nudge me in a right direction or give me a hug.

Sorry for not posting pictures, but this is as simple as a rectangle populated with random rectangles with no intersections, done by hoopsnake or anemone. I'll upload a screenshot however, as soon as get back to office.