This is one of those topics that when you get started it's hard to know where to stop, so I'm just going to give two examples now and maybe return to it later.
Everyone hates Zatanna's centipede hat. It's the crowning glory of a terrible costume design that entirely fails to fit her character or powers in any way. And yet in other circumstances it might work. For instance, if worn by the captain of an evil puppet spaceship, with the centipede so far forward that it got in their eye.
Come on down Captain Orion of Star Fleet, and show the magician how it's done!
And then there's the original costume worn by The Wasp when she first appeared. If you ever wondered what trauma caused Janet Van Dyne to become obsessive to the point of wearing a new costume in almost every issue of The Avengers, it can now be told. It was the hat. The one shaped like a wasp's sting. Of course, a wasp's sting isn't on the top of its head.
One day it occured to her that she had been fighting crime for several years wearing something that looked like an insect's rear end on her head. She's never quite recovered.