Speaking of how zebras might feel about Aslan as a Lion--
Someone--I can't remember who, had an avatar a while back ago with a pic of Aslan and it said, "Jesus, with razor-sharp claws" or something like that.
I loved that. It's like those commercials that are so great for their own sake that you always remember the commercial--the rest of your life--but you can't figure out what it advertizes.
Really I had not thought about it, regarding the Witch. With the Calormenes, it really is a culture that is being caricatured, not so much an ethnic group. It strikes me more strongly when reading about the dark-skinned Southrons in LOTR--I do squirm a little with that. But Lewis treats these issues with a little humor and subtlety.
"If you believe what you like in the Gospel, and reject what you don't like, it is not the Gospel you believe, but yourself."--St. Augustine of Hippo