The Cat in the Sorting Hat

Okay, I had a few disagreements with some of your sortings. I’m a big fan of Seussical, so this may be coloring my judgment, but I still felt I had to argue my own points.
Mayor: Hufflepuff. In the musical, he’s portrayed as very set-in-stone, as opposed to Jojo’s imagination. He does care for the kid, though. And I think he only reaches out to Horton because he wants to protect Whoville.
Sour Kangaroo: Gryffindor. Standing up for what she believes in, refusing to take no for an answer, even leading the Wickershams/Jungle Citizens in the climax!
Grinch: Slytherin. Okay, the Grinch was the monster under my bed, so I have little sympathy for him. It’s like you said with Once-ler; he’s intelligent, but uses his intelligence for his own needs and wants. And no true Ravenclaw would abuse a poor puppy!
Lorax: Hufflepuff. Yes, he uses words not blows, but I don’t think it’s because he doesn’t want to. It’s more that he’s very limited in his ability to get the message across. He does whatever he can to do just that. Sending the creatures away was not cost-benefit – he knew they would be better off someplace else.
Boy: Gryffindor. In the movie, the boy (named Ted) toes the line between Gryffindor and Ravenclaw. However, he becomes a Gryffindor by taking up the Lorax’s mantle – not because it’s the smart thing to do, but because it’s the right thing to do.
Cat: Ravenclaw. Many of your arguments for Sam-I-Am also apply here. He’s a little obsessive, very creative, and quite individualistic, a Ravenclaw trait many ignore. His status as “host and emcee” of Seussical and basically representative of all things Seuss – that is, imagination itself – only cements this.