I think your thinking of "Crazy Quilts" where various scraps - often various fabrics (lace, velvet, satin, cotton, etc) are used in whatever shape "fits" and are often embellished with embroidery, edging, beading etc.
I'm not a fan, but I need to explain.
If I'm going to make something like that, I don't want to see that each piece is the same size square. Even though the pieces are all different, I can always tell where one square ends and another starts - and they are usually made from the same size blocks.
I would handle it differently for an overall "unorganized" look using both square and rectangular blocks so that a "pattern" isn't identifiable.
I love organized patterns, but when my goal is to look unorganized I need it to look TOTALLY unorganized.