Fair enough. I've read a wide variety of comics, including manga, so for me the expressions don't seem outlandish, or the dialogue particularly hammy. But if it feels that way to you, I can see why it would be hard to read.

Maybe Cap suggested it? "Tony, I know your armor is very functional, but sometimes a superhero costume has to be more than that. It has to stand for the ideals we uphold, strike fear into the hearts of villains, and comfort civilians. I think everyone would agree that the 'A' and wings on my mask do those things. Have you ever thought of decorating your helmet?"

Or maybe just, "Tony, sky safety is very important. Add some lights so planes can see you."