If Kea can't offer anything herself, perhaps she knows of a very simple category theories for dummies paper somewhere. I've looked for Lawvere and a few others she has mentioned, but I've yet to come up with anything that is non technical. Or better yet, gives some deeper metaphysical justification for category being ultimate - like the sort of arguments that used to bandied about for set theory.
Anything on this site for a start?
Cheers - John McCrone.