Except that a flat character and an episodic plot are weaknesses even if the setting is really, really, really nifty. It may survive that, but it's best to lend some interesting to the characters, even an arc, and put some drama into the plot. Make the setting imperiled, or useful, or dangerous.
The problem with that is that it limits the amount of wonderful things you can put in, because they would distort the story's structure. And the muse, of course, does not care. Let there be a febrile city of frenetic activity, she decrees, and pools of poison, and a desert where the wind sends sand endlessly cascading, and the air smells of despair, and let the silly author figure out how to hornswoggle those into the structure that exists.