Oh yes, after seeing the community talk, I wanted to create a thread. But you beat me to it. I'll just duplicate my message from discord here:
"The problem with standard thumbnails is that they look terrible in the steam workshop. For me, as a skinmaker, this is really important. Perhaps a good solution would be to divide them into icon and icon_backgrounds, as implemented in Rust."
I'll attach a photo for comparison:image.png618.94 KB Ps, And as an additional example, black "Rockstar" glasses are not visible at all in the preview. True, this skin will need to be redone, but still.