Every people who knows Dragon Ball from the first to the 42nd Manga can say Akira Toriyama have completly changed his touch: characters have so big and squarred muscles we feel the author is drawing with a ruler. But fans of Akira know he has already drawn 18 mangas of Dr. Slump and he drew the same way all others authors of humor manga: simple and round pictures. When he began to draw DBZ, Toriyama took the "Super-Muscle" and squarred touch idea.
Like lots of authors, Akira Toriyama have aliens in his mangas. Green,
with antennas, who lay eggs with their mouth, namecks are good aliens.
But at the begining, Piccolo was not supposed to be an alien. Akira said
it in interviews, at the begining, he absolutly didn't imagine Piccolo
would be an alien and Son Goku a Saiyajin.
In fact, Piccolo was a demon. An earthling demon. The Evil Piccolo (father) and the Piccolo (son) are very different: Piccolo son doesn't have a hooked nose, he has a smooth face. Why? Because he is intended to become a good guy, instead of evil Piccolo (father) AND maybe because he is intended to be an alien.
The first apparition of Piccolo shew a big insect. See for yourself: his
head looked like the back of a queen bee, and he has these round things
on his arms they look like cocoons.
aliens are all the same: They all look like Freezer, with an almost-human
body with sometimes a carapace, and a face limitated by differrents colors.
The only exception was Cell. He looked like an instect, but his transformation
made him human.
(Left) Look at Cell: anormal mouth, none-useful wings, and horrible feet. well, a monster !
(Right) And this one? An Akira Toriyama pure touch head, with perfect teeth and a sharp nose. A human face, just like Son Gokuu and Vegeta. We could say he is good-looking :-)