Some ideas behind the sorting.

I think it's interesting how I haven't seen this mechanic widely in other games. There's physical-world analogues in postage collecting and jigsaw puzzle sorting, not to mention all other kinds of collections.

With jigsaw puzzle pieces, the sorting is focused on colors and textures. Finding a different piece is great, since it's easy to locate in the finished puzzle.

As a kid, I had a stamp collection. I remember spending so much time just sorting a mixed bag of stamps into different countries, motifs and such. It was really calming and gave a sense of accomplishment, even though the collection was probably worth next to nothing. The completed album was more of an expression of creativity than a collection of rules. With stamps, each item was also valuable - well, most likely not costing even a cent - and there was information attached, such as the face value, country of origin, and commemmorative texts. When sorting, I would remember that I had seen a similar stamp recently, and then find its sibling. Soon there might be a small family. Even copies of the same stamp were interesting, since those could be arranged by condition and slight differences.

Some notes on sorting, 10th April 2021

Even before the stamps, I sorted my grandmother's jewelry. She had a box of cheap plastic earrings, necklaces and such. Just looking at them and spreading them out on the floor in neat rows was so much fun. I was generally not a very calm child, but this kept me occupied for a long time. And my mother had a small box of buttons. I liked sorting these out to different piles, based on color and shape.

Both stamps and jigsaw puzzles are basically games we humans have created that employ the pattern-matching abilities we have. There is probably even better examples, but I can't think of any. I think humans have been sorting things for the duration of our existence, be it different sheep or pieces of dried food.

"Might make sense to keep sorting area in mid & (?) in sectors, even if they don't get the kaleidoscope-handling" from 28th February 2021. I was thinking of having each pile in one kaleidoscope segment at some point.
Yet another image about sorting. There's glyphs for each collection and the images in the collection have the border color of the associated glyph.