As Marty and Jamie suggested, I added detail to the faces of the characters and kept the text at the bottom of the poster. I am not too excited at the idea of creating facial identities for the characters, mostly because my approach to this poster was that the characters were broken down to the bare minimum. This then leads the parent to creating a connection with the child by identifying these characters together.
I definitely see that the type looks best at the bottom of the poster. My thought behind creating a block of text is simply to play off of the grid-like form within the characters.