I seriously doubt it's a fancel ^^ Fancel artists 
tend to do primo shots, head shots, and the 
like...I doubt, if someone were in it for the 
money, they would choose such an unlikely shot of 
Gally.

Also, as per the reg holes and paper 
thickness...as others have said, thickness 
varies, even in the same series. But this also 
goes for reg holes...I have sketches from Saiyuki 
that have different reg holes as well, but 
they're officially released so I know they're not 
fake. They probably ran out of a certain brand of 
cels and bought new ones, or something like 
that...nothing to get too worried about. Some 
wierd freak chance of nature ^^;;

And finally, onto differences between cel and 
sketch...the sketch may not be the final sketch 
for the cel. I have a few sequences of sketches, 
and quite a few look just like douga but differ 
from the final shot (and were made for the same 
final shot).

I hope this helps ^^

-Misha