Vortaii's design is mainly to appear comical so there are many characters that have this appeal but I focused on one type, or one person, very early on. I wanted a comical looking 'portly' man so one man that came to mind was Danny De'Vito.
The other characters that I tried to gleam personalities from are:
Shrek (predominatly from the first movie). A sort of reluctant hero that can't really be bothered except I'll tone down the heroism because he is the sidekick.
In terms of the look, I knew I wanted a Pixie as sort of guide in the vain of Navi for 'The Legend of Zelda: Ocarina of Time' so I looked at the clothing of a pixie or even a genie as it applies more to males.