I’ve had this thought for awhile that Zecora would be a great companion to 12 – a bit like Dr. Evelyn Smythe was with 6, very kind, moral, and somewhat maternal figures who aren’t afraid to rip someone a new one, including their weird alien best friend.
Also, as one friend pointed out to me, Zecora constantly talking in rhyme would both delight and annoy the hell out of 12.