Zecora is more round, thick, exotic than the ponyfolk. Y'all have to admit that. And this is artwork that closely follows the art style and proportions of the actual canon animation! It's not like it is exaggerated!
Her sexy foreign-ness reminds me of characters that Zoe Saldana portrays.
I was actually thinking about this earlier... Since Zecora's cutie mark is much bigger than other ponies, her flank is also a bit bigger, too... I don't know what to make of that, given the implications of her character.