>>113298435They had stylized character designs, but while they look like a less Vasquez Invader Zim in the 2D concept art in 3D they look like Mr. Meaty puppets in the style of Jimmy Neutron (especially the eyelids, good lord).
Copy Kitten is the only character design in the show that doesn't look ugly (even though people want to fuck Kyle he has an overbite that looks especially gross when he opens his mouth and you get to see his inflated gums).
With that, Invader Zim would look like doo-doo if it was done in the same realistic-textured stylized design FaC was.
Also while Jimmy Neutron had its ugly character designs they at least didn't have bulging eyeballs (big eyeballs yes, but never bulging).
I'd personally rank the designs like this,
Robot & Monster
Jimmy Neutron
Penguins of Madagascar
Back at the Barnyard
Fanboy & Chumhead
Planet Sheen
Monsters vs Aliens
