They are all so nice, its hard to choose. I kind of like #2, except that I probably wouldn't carve eyebrows or those diamonds next to the mouth. Too much missing pumpkin.
#3 seems more Halloweeny than the others. Kind of like a monster trying to be friendly. I think I pick #3 because too much pumpkin is missing from #2. #1 does not seem like a real pumpkin, so I don't know what that design would come out like on a real pumpkin. Hard to figure.
As presented in the pictures above, I would probably choose #3, but all of them would be nice.