that would scare the shit out of me to see piccolo giddy, giggly, and smiling really friendly!! i like his rough nature alot better. the only time when i actually saw piccolo happily laughing, and not in an evil, smart-ass or sadistic way, was when hercule had really helped save the world from buu by getting all the earthlings to cooperate with goku and give him their energy, afterwards you see piccolo standing on a ferris wheel and looking towards the sky just smiling at the fact that the same human that he considered a joke and had stolen the glory for defeating cell..actually turned out to be useful. and he was like-
piccolo: hehehe, that guy..i swear!! world champ indeed, HAHAHAHAHAHAHAHAHAHAHAHAHAHA!!!