Scepter-dodging is not Kaliko's only useful skill. He also reassembles Tik-Tok after Ruggedo breaks him in one of the Little Wizard Stories, showing a great mechanical aptitude. Rinkitink shows him working magic, but it's the only canonical book that does.
As for Kaliko's appearance, he's described as having a "fat, round body" in Emerald City, but John R. Neill usually drew him as being skinny (perhaps to present a greater contrast between him and Ruggedo), and Thompson followed suit in the text of Gnome King. And while I've heard people pronounce his name "Coleco" (like the electronics company), I'm pretty sure it's supposed to be pronounced "calico" (like the fabric or the cat). Usually, if I can find some sort of wordplay in a Baumian name, I assume it's intentional.