Well, you sort of answered your own question. ^_^ 

Cels will in the [near] future not be produced anymore. 
This means, in theory, that genga/douga will go the same 
prices as cels do now. Look at Taro's Mamotte Shu pencils, 
for instance. "Should" isn't really an issue; though I'm 
curious how much the hand-painted repros will end up going..

@_@x oro!