Re: Let The Hero Lose.
Iron Man should lose one since going gung-ho against the grain when he believes he is right and then later having a "Oh, maybe I really shouldn't have done that" moment is so in line with what his character has always been about....being human and making mistakes(sometimes really big ones). Just incorporate that into a villain winning against him for once.
MCU - $7 billion and counting. Next up: kicking Harry Potter's butt.