I've tried all kinds of luggage organizers, but generally have found them to be too restrictive (inflexible in terms of spacing, etc).
My current solution is to use those big plastic sheets (ultra thin) that your laundry comes back from the laundry/dry-cleaners in. They weigh nothing, and I use them to wrap around a collection of, say, 4 folded shirts. They don't add any structure (as they are so thin) but they do hold the clothes together as a 'unit' and enable me to lift out the 'shirt stack' and reach the 't-shirt stack'. I put a bit of blue masking tape around the edges to make the boundaries more visible.
It occurred to me that a slightly firmer plastic could be better, but not too thick. Perhaps pre-scored at various intervals to facilitate folding. I'm reminded now as I write this of some fabric / mesh organizers that had velcro 'tabs' that did allow for some variation in dimensions, and I forget now why I abandoned those in favor of my thin plastic solution.
Does anyone have any bright ideas, inspired by what I just described?! :)