Zecora is, obviously, insanely difficult to write well.
So I was delighted to read No Tame Forest, in which PhantomFox voluntarily gave Zecora's dialog a major place in the story. The rhyming may have been weak here and there, but could you have done better at that quantity of poetry? I couldn't.
I already thought that The Demesne of the Reluctant Twilight Sparkle was pretty great. (I'm not so sure I like where the relationships in that story are going, but it has enough else going on to keep me hooked.)