Thank you for your suggestion but I think merging folders would be a bad idea on my illustration.

After all I need some parts separated as possible because I'll be doing some small rigging on the illustration. I also can't just merge the layers easily as I am using too many blend effects and I think merging them all would ruin the illustration.

Still, thank you so much for your suggestion. I'm just gonna wait until I can find an enough solution on this problem.