Waley's translation might be better English than it is a perfect translation, but I wanted the swing of the story, which I got. It is almost repetitive - Monkey leaps about aggrandizing himself, with surprising success except when the Goddess Kuan Yin pulls the rug out from under him - but not quite; because Monkey learns and changes.
I don't know that he actually learns ethics, but at least he learns that he can't outsmart the Goddess of Mercy; which is in practice very similar.
The desires which he must restrain are for violence and food (and fancy clothes). No sex? (Not a bonobo, then?)
The most relevant essay I found suggests that there are several similiar, or precursor, tales in which the Monkey figure is a seducer; but that this Monkey isn't, being a Buddhist tale.
Still, the Monkey who eats and dresses up but does not swive seems rather more possible to me in a peasant tradition than a protagonist who is mad about sex but not food. (The Fall of the Kings dropped my disbelief in its archaic king-magic because there wasn't enough about food.)
Find in a Library: Monkey