It's coo' I use alot of layers too. I like to play around with my image alot before I find a look I like first, that and you know how crazy organised I am usually. Everything has its own special place. If I use only 4 or 5, I get spazzy.
I have one layer for the original sketch ['cause I sketch, scan, and PS], another layer for the white background, another for color [including shadows and highlights], and another for lines. I found a great tutorial that only used 4 layers this way and I've been Photoshopping my sketches that way ever since.