Since the main purpose of an online gallery, as I 
see it, is to give everyone the chance to enjoy 
viewing these lovely pieces of anime art, I avoid 
posting cels which just don't scan well (usually 
for reasons of color, but sometimes detail), or 
are tiny and hard to see in a halfsize scan.

If I can't do at least moderate justice to the 
artwork, I don't feel those scans are suitable for 
posting.

As for sketches, I've only posted a few... as 
other folks have already pointed out here, they're 
a total bear to scan.  ^_^  What can I say, I'm 
lazy as well as evil!